Liquid crystal display device

ABSTRACT

A liquid crystal display including a partial plate electrode along with a minute pattern in pixel electrode thereby increasing the viewing angle and the lateral visibility of the liquid crystal display, as well as the response speed A step provider is provided to reinforce the control force of the liquid crystal molecules, thereby reducing the texture generated in the center of the pixel.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of Ser. No. 13/613,331, filed on Sep.13, 2012, which claims priority from and the benefit of Korean PatentApplications No. 10-2012-0025561, filed on Mar. 13, 2012, and No.10-2012-0026073, filed on Mar. 14, 2012, all of which are herebyincorporated by reference for all purposes as if fully set forth herein.

BACKGROUND

Field

Exemplary embodiments of the present invention relate to a liquidcrystal display.

Discussion of the Background

A liquid crystal display (LCD) is one of the most widely used flat paneldisplays (FPD), and it is composed of two display panels on which fieldgenerating electrodes such as a pixel electrode and a common electrodeare formed, and a liquid crystal layer interposed between the twodisplay panels. A voltage is applied to the field generating electrodesto generate an electric field on the liquid crystal layer, and theorientation of liquid crystal molecules of the liquid crystal layer isdetermined and the polarization of incident light is controlled throughthe generated electric field to display an image.

Among these LCDs, a vertical alignment mode LCD, which arranges majoraxes of liquid crystal molecules so as to be perpendicular to thedisplay panel in a state in which an electric field is not applied, hasbeen developed.

In the vertically aligned (VA) mode liquid crystal display, it isimportant to ensure a light viewing angle, and for this purpose, amethod of forming a cutout, such as a micro-slit on the field generatingelectrode, is used. Cutouts and protrusions determine a tilt directionof liquid crystal molecules, such that a viewing angle may be increasedby appropriately disposing the cutouts and protrusions to disperse thetilt direction of the liquid crystal molecule in various directions.

In the case of forming a plurality of branch electrodes by forming theminute slits in the pixel electrode, an aperture ratio of the liquidcrystal display is reduced, and as a result, transmittance isdeteriorated.

The above information disclosed in this Background section is only forenhancement of understanding of the background of the invention andtherefore it may contain information that does not form any part of theprior art nor what the prior art may suggest to a person of ordinaryskill in the art.

SUMMARY

Exemplary embodiments of the present invention relate to a liquidcrystal display with improved transmittance and aperture ratio, andreduced texture.

Additional features of the invention will be set forth in thedescription which follows, and in part will be apparent from thedescription, or may be learned by practice of the invention.

An exemplary embodiment of the present invention discloses: a substrate;a pixel electrode including a partial plate electrode and a plurality ofminute branch electrodes extended from the partial plate electrode andformed on the substrate; and a step provider positioned between thesubstrate and the pixel electrode.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention, andtogether with the description serve to explain the principles of theinvention.

FIG. 1 is a layout view of a liquid crystal display according to anexemplary embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1.

FIG. 3 is a view showing an experimental result using the exemplaryembodiment of FIG. 1 and FIG. 2.

FIG. 4 is a layout view of a liquid crystal display according to anotherexemplary embodiment of the present invention.

FIG. 5 is a cross-sectional view taken along the line V-V of FIG. 4.

FIG. 6 is a view showing an experimental result using the exemplaryembodiment of FIG. 4 and FIG. 5.

FIG. 7 is a layout view of a liquid crystal display according to anotherexemplary embodiment of the present invention.

FIG. 8 is a cross-sectional view taken along the line VIII-VIII of FIG.7.

FIG. 9 is a view showing an experimental result using the exemplaryembodiment of FIG. 7 and FIG. 8.

FIG. 10 is a layout view of a partial wiring part in a liquid crystaldisplay according to another exemplary embodiment of the presentinvention.

FIG. 11, (b) of FIG. 12, and FIG. 14 are cross-sectional views of aliquid crystal display according to another exemplary embodiment of thepresent invention, where (a) of FIG. 12 is a layout view and (c) of FIG.12 is an experimental result using the exemplary embodiment, FIG. 13,FIG. 15, and FIG. 16 are masks used for manufacturing the liquid crystaldisplay according to another exemplary embodiment of the presentinvention.

FIG. 17 is a layout view of a liquid crystal display according toanother exemplary embodiment of the present invention.

FIG. 18 is a cross-sectional view taken along the line XVIII-XVIII ofFIG. 17.

FIG. 19 is a view showing an experimental result using the exemplaryembodiment of FIG. 17 and FIG. 18.

FIG. 20, FIG. 21, FIG. 22, FIG. 23, and FIG. 24 are enlarged views of apixel electrode of a liquid crystal display according to anotherexemplary embodiment of the present invention.

FIG. 25, FIG. 27, FIG. 29, and FIG. 31 are equivalent circuit diagramsof a liquid crystal display according to another exemplary embodiment ofthe present invention, and FIG. 26, FIG. 28, FIG. 30, and FIG. 32 arearrangement views of a liquid crystal display according to anotherexemplary embodiment of the present invention.

FIG. 33 is a layout view of a liquid crystal display according to anexemplary embodiment of the present invention.

FIG. 34 is a cross-sectional view taken along the line XXXIV-XXXIV ofFIG. 33.

FIG. 35 is an equivalent circuit diagram of one pixel of the liquidcrystal display of FIG. 33.

FIG. 36 is a layout view showing a color filter and a pixel electrode inthe liquid crystal display of FIG. 33.

FIG. 37 and FIG. 38 are views showing an experimental result using anexemplary embodiment of the present invention.

FIG. 39, FIG. 40, FIG. 41, and FIG. 42 are layout views of a partseparated from another exemplary embodiment of the present invention.

FIG. 43 is a cross-sectional view of a color filter according to anotherexemplary embodiment of the present invention.

FIG. 44 is a view of a process of providing a pretilt to liquid crystalmolecules by using a prepolymer that is polymerized by light such asultraviolet rays.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

The present invention will be described more fully hereinafter withreference to the accompanying drawings, in which embodiments of theinvention are shown. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure is thorough, and will fully convey the scope of theinvention to those skilled in the art.

In the drawings, the thickness of layers, films, panels, regions, etc.,are exaggerated for clarity. Like reference numerals designate likeelements throughout the specification. It will be understood that whenan element such as a layer, film, region, or substrate is referred to asbeing “on” or “connected to” another element, it can be directly on ordirectly connected to the other element, or intervening elements mayalso be present. In contrast, when an element is referred to as being“directly on” or “directly connected to” another element, there are nointervening elements present. It will be understood that for thepurposes of this disclosure, “at least one of X, Y, and Z” can beconstrued as X only, Y only, Z only, or any combination of two or moreitems X, Y, and Z (e.g., XYZ, XYY, YZ, ZZ}.

A liquid crystal display according to an exemplary embodiment of thepresent invention will be described with reference to FIG. 1 and FIG. 2.

FIG. 1 is a layout view of a liquid crystal display according to anexemplary embodiment of the present invention, and FIG. 2 is across-sectional view taken along the line II-II of FIG. 1.

Referring to FIG. 1 and FIG. 2, a liquid crystal display according tothe present exemplary embodiment includes a lower panel 100 and an upperpanel 200 facing each other, a liquid crystal layer 3 disposed betweenthe two display panels 100 and 200, and a pair of polarizers (not shown)attached at the outer surfaces of the display panels 100 and 200.

The lower panel 100 will be described below.

A gate line 121 and a storage voltage line 131 are formed on aninsulation substrate 110. The gate line 121 includes a first gateelectrode 124 a, a second gate electrode 124 b, and a third gateelectrode 124 c. The storage voltage line 131 includes storageelectrodes 135 a, 135 b, and 135 c, and a capacitor electrode 134extending downward. The storage voltage line 131 includes two firstlongitudinal storage electrode parts 135 a extending upward, atransverse storage electrode part 135 b connecting the two firstlongitudinal storage electrode parts 135 a, and two second longitudinalstorage electrode parts 135 c further extending upward from thetransverse storage electrode part 135 b.

The first longitudinal storage electrode part 135 a is formed along alongitudinal edge of a first sub-pixel electrode 191 h formed thereon,and the second longitudinal storage electrode part 135 c is formed alonga longitudinal edge of a second sub-pixel electrode 191 l formedthereon. The transverse storage electrode part 135 b is positionedbetween a transverse edge of the previous second sub-pixel electrode 191l and the transverse edge of the current first sub-pixel electrode 191h, and is formed along the two transverse edges.

As a result, the first longitudinal storage electrode part 135 a and thetransverse storage electrode part 135 b are formed along the edge of thefirst sub-pixel electrode 191 h, thereby at least partially overlappingthe first pixel sub-electrode 191 h, and the second longitudinal storageelectrode part 135 c and the transverse storage electrode part 135 b areformed along the edge of the second sub-pixel electrode 191 l, therebyat least partially overlapping the second sub-pixel electrode 191 l.

In FIG. 1, the overlying transverse storage electrode part 135 b and theunderlying transverse storage electrode part 135 b appear to beseparated from each other, but in actuality, transverse storageelectrode parts 135 b of the pixels PX that are adjacent up and down areelectrically connected to each other.

A gate insulating layer 140 is formed on the gate line 121 and thestorage voltage line 131. A first semiconductor 154 a, a secondsemiconductor 154 b, and a third semiconductor 154 c are formed on thegate insulating layer 140.

A plurality of ohmic contacts (not shown) are formed on the firstsemiconductor 154 a, the second semiconductor 154 b, and the thirdsemiconductor 154 c.

Data conductors 171, 173 c, 175 a, 175 b, and 175 c including aplurality of data lines 171 which include a first source electrode 173 aand a second source electrode 173 b, a first drain electrode 175 a, asecond drain electrode 175 b, a third source electrode 173 c, and athird drain electrode 175 c, are formed on the semiconductors (the firstsemiconductor 154 a, the second semiconductor 154 b, and the thirdsemiconductor 154 c), the ohmic contacts (not shown), and the gateinsulating layer 140.

The first gate electrode 124 a, the first source electrode 173 a, andthe first drain electrode 175 a form a first thin film transistor Qatogether with the first semiconductor 154 a, and a channel of the firstthin film transistor Qa is formed in the semiconductor 154 a between thefirst source electrode 173 a and the first drain electrode 175 a.Similarly, the second gate electrode 124 b, the second source electrode173 b, and the second drain electrode 175 b form a second thin filmtransistor Qb together with the second semiconductor 154 b, a channel ofthe second thin film transistor Qb is formed in the semiconductorportion 154 b between the second source electrode 173 b and the seconddrain electrode 175 b, the third gate electrode 124 c, the third sourceelectrode 173 c, and the third drain electrode 175 c form a third thinfilm transistor Qc together with the third semiconductor 154 c, and achannel of the third thin film transistor Qc is formed in thesemiconductor 154 c between the third source electrode 173 c and thethird drain electrode 175 c.

A color filter 230 and a passivation layer 180 are sequentially formedon the gate insulating layer 140, the data conductors 171, 173 c, 175 a,175 b, and 175 c, and exposed portions of the semiconductors 154 a, 154b, and 154 c. The color filter 230 may display one of three primarycolors such, as red, green, and blue, but it is not limited to displayof a primary color and may also display one of cyan, magenta, yellow,and white-based colors. Meanwhile, the passivation layer 180 may beformed of an insulator, such as silicon nitride and silicon oxide, or aninsulator, and in the exemplary embodiment of FIG. 1, the organicinsulating layer including the insulator is described.

A step provider providing a step to an overlying layer is formed in thepassivation layer 180 of the insulator, and in FIG. 1, step providinggrooves 185 h and 185 l and a cross-shaped protrusion 182 positionedbetween the step providing grooves 185 h and 185 l function as the stepprovider. As shown in FIG. 1, the step providing grooves 185 h and 185 lhave a right triangle structure and are symmetrical to each other in adiagonal direction. As a result, the passivation layer 180 includes thecross-shaped protrusion 182.

The color filter 230 and the passivation layer 180 include a firstcontact hole 184 a, a second contact hole 184 b, and a third contacthole 184 c respectively exposing the first drain electrode 175 a, thesecond drain electrode 175 b, and the third drain electrode 175 c. Thepassivation layer 180 includes an opening 189 collecting a gas emittedfrom the color filter 230. According to FIG. 1, one pixel may include apair of openings 189.

A pixel electrode 191 including the first subpixel electrode 191 h andthe second subpixel electrode 191 l is formed on the passivation layer180. The first subpixel electrode 191 h and the second subpixelelectrode 191 l respectively include partial plate electrodes 192 h and192 l positioned at a center thereof, and a plurality of minute branchelectrodes 193 h and 193 l protruding from the partial plate electrodes192 h and 192 l in an oblique direction.

The first subpixel electrode 191 h includes the first partial plateelectrode 192 h and a plurality of first minute branch electrodes 193 hpositioned in the square region, and is connected to a wide end portionof the first drain electrode 175 a by a first minute branch connection194 h extending outside the square region.

The first partial plate electrode 192 h has a rhombus shape, a centerthereof is positioned at a center of the square region, and each vertexof the rhombus meets the boundary of the square region. The firstpartial plate electrode 192 h covers the first step providing groove 185h of the passivation layer 180 and a first cross-shaped protrusion 182h. As a result, the first partial plate electrode 192 h has a stepprovided by the first step providing groove 185 h of the passivationlayer 180 and the first cross-shaped protrusion 182 h. Here, the firstcross-shaped protrusion 182 h provides a pretilt to liquid crystalmolecules positioned at the center of the square region. therebyfunctioning to control an arrangement direction of the liquid crystalmolecules, and as a result, the texture is reduced.

A plurality of first minute branch electrodes 193 h are extended at anedge of the oblique direction of the first partial plate electrode 192h. The plurality of first minute branch electrode 193 h fill the rest ofthe square region, form an angle of 45 degrees with respect to the gateline 121 or the data line 171, and form an angle of 90 degrees withrespect to the edge of the oblique direction of the first partial plateelectrode 192 h.

In the exemplary embodiment of the present invention shown in FIG. 1,the first subpixel electrode 191 h includes a first minute branchconnection 194 h connecting the first partial plate electrode 192 h andthe ends of a plurality of first minute branch electrodes 193 h in alongitudinal direction or a horizontal direction. The first minutebranch connection 194 h overlaps the first subpixel electrode 191 h andthe underlying storage electrode 135 a and 135 b, thereby forming astorage capacitance. However, according to an exemplary embodiment ofthe present invention, the first minute branch connection 194 h may beomitted, and in this case, a plurality of first minute branch electrodes193 h protrude to the outside.

The second subpixel electrode 191 l includes the second partial plateelectrode 192 l and a plurality of second minute branch electrodes 193 lformed in the rectangle region having a longitudinal edge, and isconnected to the wide end portion of the second drain electrode 175 l bya second minute branch connection 194 l extended outside the rectangleregion.

The center of the second partial plate electrode 192 l is positioned atthe center of the rectangle region and has the rhombus shape connectingthe center of each edge of the rectangle region. As a result, eachvertex of the rhombus meets the boundary of the rectangle region, andthe second partial plate electrode 192 l has a greater width in thevertical direction than the horizontal direction. The second partialplate electrode 192 l covers the second step providing groove 185 l ofthe passivation layer 180 and a second cross-shaped protrusion 182 l. Asa result, the second partial plate electrode 192 l has the step providedby the second step providing groove 185 l of the passivation layer 180and the second cross-shaped protrusion 182 l of the cross type. Aplurality of second minute branch electrodes 193 l extend from the edgeof the oblique direction of the second partial plate electrode 192 l.The plurality of second minute branch electrodes 193 l fill the rest ofthe rectangle region, form an angle of 45 degrees with respect to thegate line 121 or the data line 171, and form an angle of 90±15 degreeswith respect to the edge of the oblique direction of the second partialplate electrode 192 l.

Meanwhile, in the exemplary embodiment of FIG. 1, the second subpixelelectrode 191 l includes the second minute branch connection 194 lconnecting the second partial plate electrode 192 l and the ends of aplurality of second minute branch electrode 193 l in a longitudinaldirection or a horizontal direction. The second minute branch connection194 l overlaps the second subpixel electrode 191 l and the underlyingstorage electrode 135 b and 135 c, thereby forming a storagecapacitance. However, according to an exemplary embodiment of thepresent invention, the second minute branch connection 194 l may beomitted, and in this case, a plurality of second minute branchelectrodes 193 l protrude outside.

The first subpixel electrode 191 h and the second subpixel electrode 191l are physically and electrically connected to the first drain electrode175 a and the second drain electrode 175 b through the contact holes 184a and 184 b, thereby receiving data voltages from the first drainelectrode 175 a and the second drain electrode 175 b. At this time, theportion of the data voltage applied to the second drain electrode 175 bis divided through the third source electrode 173 c, such that amagnitude of the voltage applied to the second subpixel electrode 191 lis less than the magnitude of the voltage applied to the first subpixelelectrode 191 h. Here, an area of the second subpixel electrode 191 lmay be approximately one to two times less than that of the firstsubpixel electrode 191 h.

A storage electrode connecting member 139 connects the capacitorelectrode 134 of the storage voltage line 131 and the third drainelectrode 175 c through the contact hole 184 c. The storage voltage Vcstis applied to the capacitor electrode 134 of the storage voltage line131 to have a predetermined voltage, thereby apply the storage voltageVcst to the third thin film transistor Qc through the third drainelectrode 175 c. As a result, the voltage applied to the secondsub-pixel may be decreased.

A cover 199 covering the opening 189 of the passivation layer 180 isformed on the opening 189. The cover 199 is formed to block transmissionof a gas emitted from the color filter 230 to other elements, andaccording to FIG. 1, one pixel may include a pair of covers 199. Thepixel electrode 191 and the cover 199 may be made of a transparentconductive material such as ITO or IZO. Accordingly to an exemplaryembodiment of the present invention, the opening 189 and the cover 199may be omitted.

A lower alignment layer (not shown) is formed on the pixel electrodes191. The lower alignment layer may be a vertical alignment layer and maybe the alignment layer including a photo-reactive material. Thephoto-reactive material will be described with reference to FIG. 44.

The common electrode panel 200 will be described below.

A light blocking member 220 is formed on an insulation substrate 210.The light blocking member 220 is referred to as black matrix andprevents light leakage. The light blocking member 220 extends along thegate line 121, covers a region where the first thin film transistor(Qh), the second thin film transistor (Ql), and the third thin filmtransistor (Qc) are positioned, is extended along the data line 171, andcovers the surroundings of the data line 171. A region that is notcovered by the light blocking member 220 emits light to the outside,thereby displaying the images.

A planarization layer 250 providing a planar lower surface and made oforganic material is formed under the light blocking member 220.

A common electrode 270 made of the transparent conductive material isformed under the planarization layer 250.

An upper alignment layer (not shown) may be formed under the commonelectrode 270. The upper alignment layer may be a vertical alignmentlayer and may be an alignment layer in which a photo-polymer material isphoto-aligned.

Polarizers (not shown) are formed on the outer surface of the displaypanels 100 and 200, the polarization axis of the two polarizers arecrossed, and one polarization axis thereof may be parallel to the gatelines 121. The polarizer may be disposed on one outer surface among thetwo display panels 100 and 200.

The first subpixel electrode 191 h and the second subpixel electrode 191l to which the data voltage is applied generate an electric field inconjunction with the common electrode 270 of the common electrode panel200 such that the liquid crystal molecules of the liquid crystal layer 3that are aligned vertically to the surface of two electrodes 191 and 270in the absence of the electric field are slanted in a direction parallelto the surface of the two electrodes 191 and 270, and thereby theluminance of the light transmitted through the liquid crystal layer 3differs depending on the slant degree of the liquid crystal molecules.

The liquid crystal display may further include a spacer (not shown) tomaintain a cell interval between the two display panels 100 and 200, andthe spacer may be attached to either the upper panel 200 or the lowerpanel 100.

The liquid crystal layer 3 disposed between the lower panel 100 and theupper panel 200 includes the liquid crystal molecules 31 having negativedielectric anisotropy.

The liquid crystal layer 3 or the alignment layer (not shown) mayfurther include a polymer that is polymerized by light, such asultraviolet rays. The polymer included in the liquid crystal layer 3provides the pretilt to the liquid crystal layer 3, and a method ofproviding the pretilt angle will be described in detail in FIG. 44. Thatis, the liquid crystal layer 3 may not include the polymer when thearrangement direction is sufficiently controlled without the polymerproviding the pretilt angle.

As described above, in the exemplary embodiment of FIG. 1 and FIG. 2,the step provider is formed in the passivation layer 180 of theinsulator and includes the step providing grooves 185 h and 185 l andthe cross-shaped protrusions 182 h and 182 l positioned between the stepproviding grooves 185 h and 185 l.

However, the texture is reduced the most according to the provided step(referring to d of FIG. 2), thereby increasing the transmittance, withreference to FIG. 3.

FIG. 3 is a view showing an experimental result using the exemplaryembodiment of FIG. 1 and FIG. 2.

In FIG. 3, “Passi” means the passivation layer 180 of the insulator, andthe two upper pictures in FIG. 3 are a case where the passivation layer180 of the insulator is formed with a thickness of 1000 Å, while the twolower pictures in FIG. 3 are a case where the passivation layer 180 ofthe insulator is formed with a thickness of 4000 Å.

In FIG. 3, when providing the step via the step providing groove and thecross-shaped protrusion, as in the exemplary embodiment of FIG. 1 andFIG. 2, the texture may be not controlled and the transmittance isdecreased when a step of 1000 Å is provided, but the texture may becontrolled and the transmittance is increased when a step of 4000 Å isprovided. When providing the step via the step providing groove and thecross-shaped protrusion, as in the exemplary embodiment of FIG. 1 andFIG. 2, it may be confirmed that the control force of the liquid crystalmolecules is reinforced when the step is large such that the texture isdecreased, and the texture is decreased when the step is more than 3000Å such that the transmittance is greater than a predetermined degree.

In the exemplary embodiment of FIG. 1 and FIG. 2, the passivation layer180 of the insulator includes the step providing groove and thecross-shaped protrusion. However, the step providing groove and thecross-shaped protrusion may be formed in the color filter 230. Thepassivation layer 180 on the color filter 230 may be formed of aninorganic insulating material or may be omitted. Although the stepprovider is formed by using the step providing groove and thecross-shaped protrusion of the color filter 230, as shown in FIG. 3, astep of more than 3000 Å must be provided to reduce the texture.

Next, another exemplary embodiment of the present invention will bedescribed with reference to FIG. 4 to FIG. 6.

FIG. 4 is a layout view of a liquid crystal display according to anotherexemplary embodiment of the present invention, and FIG. 5 is across-sectional view taken along the line V-V of FIG. 4.

The exemplary embodiment of FIG. 4 and FIG. 5 is a case of formingcross-shaped grooves 182-1 h and 182-1 l as the step provider, whichdiffers from the exemplary embodiment of FIG. 1 and FIG. 2.

Referring to FIG. 4 and FIG. 5, the liquid crystal display according tothe present exemplary embodiment includes the lower panel 100 and theupper panel 200 facing each other, a liquid crystal layer 3 disposedbetween the two display panels 100 and 200, and a pair of polarizers(not shown) attached at the outer surfaces of the display panels 100 and200. The upper panel 200 of the exemplary embodiment of FIG. 4 and FIG.5 is the same as that of FIG. 1 and FIG. 2 such that the descriptionthereof is omitted.

The lower panel 100 will be described, and the layered structure fromthe insulation substrate 110 to the color filter 230 in the lower panel100 is the same as the exemplary embodiment of FIG. 1 and FIG. 2.

The gate line 121 and the storage voltage line 131 are formed on theinsulation substrate 110. The gate line 121 includes a first gateelectrode 124 a, a second gate electrode 124 b, and a third gateelectrode 124 c. The storage voltage line 131 includes storageelectrodes 135 a, 135 b, and 135 c, and a capacitor electrode 134extending downward. The storage voltage line 131 includes two firstlongitudinal storage electrode parts 135 a extending upward, atransverse storage electrode part 135 b connecting two firstlongitudinal storage electrode parts 135 a, and two second longitudinalstorage electrode parts 135 c further extending upward from thetransverse storage electrode part 135 b.

The first longitudinal storage electrode part 135 a is formed along alongitudinal edge of the first sub-pixel electrode 191 h formed thereon,and the second longitudinal storage electrode part 135 c is formed alongthe longitudinal edge of the second sub-pixel electrode 191 l formedthereon. Meanwhile, the transverse storage electrode part 135 b ispositioned between a transverse edge of the previous second sub-pixelelectrode 191 l and the transverse edge of the current first sub-pixelelectrode 191 h, and is formed along the two transverse edges.

As a result, the first longitudinal storage electrode part 135 a and thetransverse storage electrode part 135 b are formed along the edge of thefirst sub-pixel electrode 191 h, thereby at least partially overlappingthe first sub-pixel electrode 191 h, and the second longitudinal storageelectrode part 135 c and the transverse storage electrode part 135 b areformed along the edge of the second sub-pixel electrode 191 l, therebyat least partially overlapping the second sub-pixel electrode 191 l.

In FIG. 4, the overlying transverse storage electrode part 135 b and theunderlying transverse storage electrode part 135 b appear to beseparated from each other, but in actuality, the transverse storageelectrode parts 135 b of the pixels PX that are adjacent up and down areelectrically connected to each other.

The gate insulating layer 140 is formed on the gate line 121 and thestorage voltage line 131. The first semiconductor 154 a, the secondsemiconductor 154 b, and the third semiconductor 154 c are formed on thegate insulating layer 140.

A plurality of ohmic contacts (not shown) may be formed on the firstsemiconductor 154 a, the second semiconductor 154 b, and the thirdsemiconductor 154 c.

Data conductors 171, 173 c, 175 a, 175 b, and 175 c including aplurality of data lines 171 which include the first source electrode 173a and the second source electrode 173 b, the first drain electrode 175a, the second drain electrode 175 b, the third source electrode 173 c,and the third drain electrode 175 c, are formed on the semiconductor(the first semiconductor 154 a, the second semiconductor 154 b, and thethird semiconductor 154 c), the ohmic contacts (not shown), and the gateinsulating layer 140.

The first gate electrode 124 a, the first source electrode 173 a, andthe first drain electrode 175 a form a first thin film transistor Qatogether with the first semiconductor 154 a, and a channel of the firstthin film transistor Qa is formed in the semiconductor portion 154 abetween the first source electrode 173 a and the first drain electrode175 a. Similarly, the second gate electrode 124 b, the second sourceelectrode 173 b, and the second drain electrode 175 b form a second thinfilm transistor Qb together with the second semiconductor 154 b, achannel of the second thin film transistor Qb is formed in thesemiconductor portion 154 b between the second source electrode 173 band the second drain electrode 175 b, the third gate electrode 124 c,the third source electrode 173 c, and the third drain electrode 175 cform a third thin film transistor Qc together with the thirdsemiconductor 154 c, and a channel of the third thin film transistor Qcis formed in the semiconductor portion 154 c between the third sourceelectrode 173 c and the third drain electrode 175 c.

The color filter 230 and the passivation layer 180 are sequentiallyformed on the gate insulating layer 140, the data conductors 171, 173 c,175 a, 175 b, and 175 c, and the exposed portion of the semiconductors154 a, 154 b, and 154 c. The color filter 230 may display one of threeprimary colors such as red, green, and blue, but it is not limited todisplay of a primary color and may also display and may display one ofcyan, magenta, yellow, and white-based colors. Meanwhile, thepassivation layer 180 may be formed of an insulator such as siliconnitride and silicon oxide, or an insulator, and in the exemplaryembodiment of FIG. 1, the organic insulating layer including theinsulator is described.

The step provider providing the step to the overlying layer is formed inthe passivation layer 180 of the insulator, and in FIG. 4, thecross-shaped grooves 182-1 h and 182-1 l are the only step provider. Thecross-shaped grooves 182-1 h and 182-1 l are formed with a predetermineddepth d while having the cross shape, as shown in FIG. 4 and FIG. 5. InFIG. 5, the cross-shaped grooves 182-1 h and 182-1 l of the stepprovider are formed by entirely etching the passivation layer 180 of theinsulator such that the color filter 230 is formed directly under thecross-shaped grooves 182-1 h and 182-1 l without the passivation layer180, although the passivation layer 180 may have a predeterminedthickness according to an exemplary embodiment of the present invention.

The color filter 230 and the passivation layer 180 include the firstcontact hole 184 a, the second contact hole 184 b, and the third contacthole 184 c respectively exposing the first drain electrode 175 a, thesecond drain electrode 175 b, and the third drain electrode 175 c.

The pixel electrode 191, including the first subpixel electrode 191 hand the second subpixel electrode 191 l, is formed on the passivationlayer 180. The first subpixel electrode 191 h and the second subpixelelectrode 191 l respectively include partial plate electrodes 192 h and192 l positioned at a center thereof, and a plurality of minute branchelectrodes 193 h and 193 l protruding from the partial plate electrode192 h and 192 l in an oblique direction.

The first subpixel electrode 191 h includes the first partial plateelectrode 192 h and a plurality of first minute branch electrodes 193 hpositioned in the square region, and is connected to a wide end portionof the first drain electrode 175 a by the first minute branch connection194 h extending outside the square region.

The first partial plate electrode 192 h has a rhombus shape, a centerthereof is positioned at a center of the square region, and each vertexof the rhombus meets the boundary of the square region. Also, the firstpartial plate electrode 192 h covers the first cross-shaped groove 182-1h of the passivation layer 180. As a result, the first partial plateelectrode 192 h has the step provided by the first cross-shaped groove182-1 h of the passivation layer 180, as illustrated in FIG. 5. Here,the first cross-shaped groove 182-1 h provides the pretilt to the liquidcrystal molecules positioned at the center of the square region, therebycontrolling the arrangement direction of the liquid crystal moleculesand, as a result, the reducing the texture.

A plurality of first minute branch electrodes 193 h extend to an edge ofthe oblique direction of the first partial plate electrode 192 h. Aplurality of first minute branch electrodes 193 h fill the rest of thesquare region, form an angle of 45 degrees with respect to the gate line121 or the data line 171, and form an angle of 90 degrees with respectto the edge of the oblique direction of the first partial plateelectrode 192 h.

Meanwhile, in the exemplary embodiment of FIG. 4, the first subpixelelectrode 191 h includes the first minute branch connection 194 hconnecting the first partial plate electrode 192 h and the ends of aplurality of first minute branch electrodes 193 h in a longitudinaldirection or a horizontal direction. The first minute branch connection194 h overlaps the first subpixel electrode 191 h and the underlyingstorage electrode 135 a and 135 b, thereby forming the storagecapacitance. However, according to an exemplary embodiment of thepresent invention, the first minute branch connection 194 h may beomitted, and in this case, a plurality of first minute branch electrodes193 h protrude to the outside.

On the other hand, the second subpixel electrode 191 l includes thesecond partial plate electrode 192 l and a plurality of second minutebranch electrodes 193 l formed in the rectangle region having alongitudinal edge, and is connected to the wide end portion of thesecond drain electrode 175 l by the second minute branch connection 194l extending outside the rectangle region.

The center of the second partial plate electrode 192 l is positioned atthe center of the rectangle region, and has a rhombus shape connectingthe center of each edge of the rectangle region. As a result, eachvertex of the rhombus meets the boundary of the rectangle region. Inaddition, the second partial plate electrode 192 l covers the secondcross-shaped groove 182-1 l of the passivation layer 180. As a result,the second partial plate electrode 192 l has the step provided by thesecond cross-shaped groove 182-1 l of the passivation layer 180, asillustrated in FIG. 5.

A plurality of second minute branch electrodes 193 l extend from theedge of the oblique direction of the second partial plate electrode 192l. The plurality of second minute branch electrodes 193 l fills the restof the rectangle region, form an angle of 45 degrees with respect to thegate line 121 or the data line 171, and form an angle of 90±15 degreeswith respect to the edge of the oblique direction of the second partialplate electrode 192 l.

In the exemplary embodiment of FIG. 4, the second subpixel electrode 191l includes the second minute branch connection 194 l connecting thesecond partial plate electrode 192 l and the ends of a plurality ofsecond minute branch electrodes 193 l in a longitudinal direction or ahorizontal direction. The second minute branch connection 194 l overlapsthe second subpixel electrode 191 l and the underlying storageelectrodes 135 b and 135 c, thereby forming the storage capacitance.However, according to an exemplary embodiment, the second minute branchconnection 194 l may be omitted, and in this case, a plurality of secondminute branch electrodes 193 l protrude to the outside.

The first subpixel electrode 191 h and the second subpixel electrode 191l are physically and electrically connected to the first drain electrode175 a and the second drain electrode 175 b through the contact holes 184a and 184 b, thereby receiving data voltages from the first drainelectrode 175 a and the second drain electrode 175 b. At this time, theportion of the data voltage applied to the second drain electrode 175 bis divided through the third source electrode 173 c such that amagnitude of the voltage applied to the second subpixel electrode 191 lis less than the magnitude of the voltage applied to the first subpixelelectrode 191 h. Here, an area of the second subpixel electrode 191 lmay be approximately one to two times less than that of the firstsubpixel electrode 191 h.

A lower alignment layer (not shown) is formed on the pixel electrodes191. The lower alignment layer may be a vertical alignment layer, andmay be an alignment layer including a photo-reactive material. Thephoto-reactive material will be described with reference to FIG. 44.

As described above, in the exemplary embodiment of FIG. 4 and FIG. 5,the step provider is formed in the passivation layer 180 of theinsulator and is made of the cross-shaped grooves 182-1 h and 182-1 l.

However, the texture is most reduced according to the provided step(referring to d of FIG. 5), thereby increasing the transmittance withreference to FIG. 6.

FIG. 6 is a view showing an experimental result using the exemplaryembodiment of FIG. 4 and FIG. 5.

In FIG. 6, “passi” refers to the passivation layer 180 of the insulator,and “Nega” refers to the cross-shaped groove formed as the stepprovider. As shown in FIG. 6, as the depth of the cross-shaped groove isincreased, the control force controlling the liquid crystal moleculesbecomes weaker such that the texture is largely generated. Therefore, ifthe depth of the cross-shaped groove is small when forming thecross-shaped groove as the step provider, the texture is decreased andthe depth of 3000 Å is preferable.

In the exemplary embodiment of FIG. 4 and FIG. 5, although thecross-shaped groove as the step provider is formed in the passivationlayer 180 of the insulator, an exemplary embodiment forming thecross-shaped groove in the color filter 230 is possible. The passivationlayer 180 on the color filter 230 may be formed of an inorganicinsulating material or may be omitted. Although the cross-shaped grooveas the step provider is formed in the color filter 230, as shown in FIG.6, a step of less than 3000 Å must be provided to reduce the texture.The cross-shaped groove must have a minimum depth, and a depth of morethan 100 Å is preferable.

Next, another exemplary embodiment of the present invention will bedescribed with reference to FIG. 7 to FIG. 9.

FIG. 7 is a layout view of a liquid crystal display according to anotherexemplary embodiment of the present invention, and FIG. 8 is across-sectional view taken along the line VIII-VIII of FIG. 7.

In the exemplary embodiment of FIG. 7 and FIG. 8, as opposed to theexemplary embodiments of FIG. 1, FIG. 2, FIG. 4, and FIG. 5, stepproviding wiring is formed with the same layer as the gate line as thestep provider, and thereby the step is generated in the overlyinginsulating layer/passivation layer as a result of the thickness of thestep providing wiring.

In the exemplary embodiment of FIG. 7 and FIG. 8, as opposed to theexemplary embodiments of FIG. 1, FIG. 2, FIG. 4, and FIG. 5, the colorfilter 230 is not formed in the lower panel 100, but is formed in theupper panel 200. In the present exemplary embodiment, the color filter230 may be formed in the lower panel 100, although the color filter 230may be formed lower (a side of the substrate) than the wiring providingthe step. This is because the step provided by the step providing wiringmay not be generated at the position of the pixel electrode because ofthe planarization characteristic of the color filter 230 when formingthe color filter 230 on the wiring such as the gate line. Also, formingthe insulating layer/passivation layer including the inorganic materialon the wiring, such as the gate line, as compared with the passivationlayer/insulating layer including the organic material, may transmit thestep provided by the step providing wiring to the position where thepixel electrode is formed as it is. As a result, in the exemplaryembodiment of FIG. 7 and FIG. 8, the gate insulating layer 140 and thepassivation layer 180 are formed of the inorganic material.

Referring to FIG. 7 and FIG. 8, the liquid crystal display according tothe present exemplary embodiment includes the lower panel 100 and theupper panel 200 facing each other, a liquid crystal layer 3 interposedbetween the two display panels 100 and 200, and a pair of polarizers(not shown) attached at the outer surfaces of the display panels 100 and200.

First, the lower panel 100 will be described.

The gate line 121, the storage voltage line 131, and the step providingwires 132 h and 132 l are formed on the insulation substrate 110. Thegate line 121 includes a first gate electrode 124 a, a second gateelectrode 124 b, and a third gate electrode 124 c. The storage voltageline 131 includes storage electrodes 135 a, 135 b, and 135 c, and acapacitor electrode 134 extending downward. The storage voltage line 131includes two first longitudinal storage electrode parts 135 a extendingupward, a transverse storage electrode part 135 b connecting two firstlongitudinal storage electrode parts 135 a, and two second longitudinalstorage electrode parts 135 c further extending upward from thetransverse storage electrode part 135 b. The first longitudinal storageelectrode part 135 a is formed along a longitudinal edge of the firstsub-pixel electrode 191 h formed thereon, and the second longitudinalstorage electrode part 135 c is formed along the longitudinal edge ofthe second sub-pixel electrode 191 l formed thereon. Meanwhile, thetransverse storage electrode part 135 b is positioned between atransverse edge of the previous second sub-pixel electrode 191 l and thetransverse edge of the current first sub-pixel electrode 191 h, and isformed along the two transverse edges. As a result, the firstlongitudinal storage electrode part 135 a and the transverse storageelectrode part 135 b are formed along the edge of the first sub-pixelelectrode 191 h, thereby at least partially overlapping the firstsub-pixel electrode 191 h, and the second longitudinal storage electrodepart 135 c and the transverse storage electrode part 135 b are formedalong the edge of the second sub-pixel electrode 191 l, thereby at leastpartially overlapping the second sub-pixel electrode 191 l. In FIG. 1,the overlying transverse storage electrode part 135 b and the underlyingtransverse storage electrode part 135 b appear to be separated from eachother, but in actuality, the transverse storage electrode part 135 b ofthe pixels PX that are adjacent up and down are electrically connectedto each other.

The step providing wires 132 h and 132 l are formed with the same layerand the same material as the gate line 121 and the storage voltage line131 in the exemplary embodiment of FIG. 7, and are electricallyconnected to the storage electrodes 135 a, 135 b, and 135 c of thestorage voltage line 131. That is, the first step providing wire 132 hhas a cross shape, and four ends are respectively connected to the firstlongitudinal storage electrode part 135 a, the transverse storageelectrode part 135 b, and the storage voltage line 131. Meanwhile, thesecond step providing wire 132 l has a cross shape, and three of fourends are respectively connected to the second longitudinal storageelectrode part 135 c and the transverse storage electrode part 135 b,and the remaining end is not connected.

The step providing wires 132 h and 132 l have a predetermined thicknessto provide the step to the overlying insulating layer/passivation layer,as will be described with reference to FIG. 9.

The gate insulating layer 140 made of the inorganic insulating materialis formed on the gate line 121, the storage voltage line 131, and thestep providing wires 132 h and 132 l. The first semiconductor 154 a, thesecond semiconductor 154 b, and the third semiconductor 154 c are formedon the gate insulating layer 140.

The plurality of ohmic contacts (not shown) are formed on the firstsemiconductor 154 a, the second semiconductor 154 b, and the thirdsemiconductor 154 c.

Data conductors 171, 173 c, 175 a, 175 b, and 175 c including aplurality of data lines 171 which include the first source electrode 173a and the second source electrode 173 b, the first drain electrode 175a, the second drain electrode 175 b, the third source electrode 173 c,and the third drain electrode 175 c, are formed on the semiconductor(the first semiconductor 154 a, the second semiconductor 154 b, and thethird semiconductor 154 c), the ohmic contacts (not shown), and the gateinsulating layer 140.

The first gate electrode 124 a, the first source electrode 173 a, andthe first drain electrode 175 a form a first thin film transistor Qatogether with the first semiconductor 154 a, and a channel of the firstthin film transistor Qa is formed in the semiconductor portion 154 abetween the first source electrode 173 a and the first drain electrode175 a. Similarly, the second gate electrode 124 b, the second sourceelectrode 173 b, and the second drain electrode 175 b form a second thinfilm transistor Qb together with the second semiconductor 154 b, achannel of the second thin film transistor Qb is formed in thesemiconductor portion 154 b between the second source electrode 173 band the second drain electrode 175 b, the third gate electrode 124 c,the third source electrode 173 c, and the third drain electrode 175 cform a third thin film transistor Qc together with the thirdsemiconductor 154 c, and a channel of the third thin film transistor Qcis formed in the semiconductor portion 154 c between the third sourceelectrode 173 c and the third drain electrode 175 c.

The passivation layer 180 is formed on the gate insulating layer 140,the data conductors 171, 173 c, 175 a, 175 b, and 175 c, and the exposedportion of the semiconductors 154 a, 154 b, and 154 c. The passivationlayer 180 is formed of the insulator, such as silicon nitride andsilicon oxide, thereby maintaining the step provided by the stepproviding wires 132 h and 132 l without planarization. As a result, thecross-shaped step corresponding to the shape of the step providing wires132 h and 132 l is formed on the passivation layer 180, and hereafter, aportion where the step is formed on the passivation layer 180 isreferred to as “a wiring providing step part”.

The passivation layer 180 of the inorganic insulating layer includes thefirst contact hole 184 a, the second contact hole 184 b, and the thirdcontact hole 184 c respectively exposing the first drain electrode 175a, the second drain electrode 175 b, and the third drain electrode 175c.

The pixel electrode 191, including the first subpixel electrode 191 hand the second subpixel electrode 191 l, is formed on the passivationlayer 180. The first subpixel electrode 191 h and the second subpixelelectrode 191 l respectively include partial plate electrodes 192 h and192 l positioned at a center thereof, and a plurality of minute branchelectrodes 193 h and 193 l protruding from the partial plate electrode192 h and 192 l in an oblique direction.

The first subpixel electrode 191 h includes the first partial plateelectrode 192 h and a plurality of first minute branch electrodes 193 hpositioned in the square region, and is connected to a wide end portionof the first drain electrode 175 a by the first minute branch connection194 h extending outside the square region.

The first partial plate electrode 192 h has a rhombus shape, a centerthereof being positioned at a center of the square region, and eachvertex of the rhombus meets the boundary of the square region. The firstpartial plate electrode 192 h covers the first wiring providing steppart generated in the passivation layer 180 by the first step providingwire 132 h. As a result, the first partial plate electrode 192 h has thestep provided by the first wiring providing step part of the passivationlayer 180. Referring to FIG. 8, the first wiring providing step partprovides the pretilt to the liquid crystal molecules positioned at thecenter of the square region, thereby controlling the arrangementdirection of the liquid crystal molecules, and as a result, reducing thetexture.

A plurality of first minute branch electrodes 193 h extend in an edge ofthe oblique direction of the first partial plate electrode 192 h. Theplurality of first minute branch electrodes 193 h fill the rest of thesquare region, form an angle of 45 degrees with respect to the gate line121 or the data line 171, and form an angle of 90 degrees with respectto the edge of the oblique direction of the first partial plateelectrode 192 h.

Meanwhile, in the exemplary embodiment of FIG. 7, the first subpixelelectrode 191 h includes the first minute branch connection 194 hconnecting the first partial plate electrode 192 h and the ends of aplurality of the first minute branch electrodes 193 h in a longitudinaldirection or a horizontal direction. The first minute branch connection194 h overlaps the first subpixel electrode 191 h and the underlyingstorage electrodes 135 a and 135 b, thereby forming a storagecapacitance. However, according to an exemplary embodiment of thepresent invention, the first minute branch connection 194 h may beomitted, and in this case, a plurality of first minute branch electrodes193 h protrude to the outside.

The second subpixel electrode 191 l includes the second partial plateelectrode 192 l and a plurality of second minute branch electrodes 193 lformed in the rectangle region having a longitudinal edge, and isconnected to the wide end portion of the second drain electrode 175 l bythe second minute branch connection 194 l extending outside therectangle region.

The center of the second partial plate electrode 192 l is positioned atthe center of the rectangle region, and has a rhombus shape connectingthe center of each edge of the rectangle region. As a result, eachvertex of the rhombus meets the boundary of the rectangle region. Also,the second partial plate electrode 192 l covers the second wiringproviding step part generated in the passivation layer 180 by the secondstep providing wires 132 l. As a result, the second partial plateelectrode 192 l has the step provided by the second wiring providingstep part of the passivation layer 180, as illustrated in FIG. 8.

A plurality of second minute branch electrodes 193 l extend from theedge of the oblique direction of the second partial plate electrode 192l. A plurality of second minute branch electrodes 193 l fill the rest ofthe rectangle region, form an angle of 45 degrees with respect to thegate line 121 or the data line 171, and form an angle of 90±15 degreeswith respect to the edge of the oblique direction of the second partialplate electrode 192 l.

In the exemplary embodiment of FIG. 4, the second subpixel electrode 191l includes the second minute branch connection 194 l connecting thesecond partial plate electrode 192 l and the ends of a plurality ofsecond minute branch electrodes 193 l in a longitudinal direction or ahorizontal direction. The second minute branch connection 194 l overlapsthe second subpixel electrode 191 l and the underlying storage electrode135 b and 135 c, thereby forming a storage capacitance. However,according to an exemplary embodiment of the present invention, thesecond minute branch connection 194 l may be omitted, and in this case,a plurality of second minute branch electrodes 193 l protrude to theoutside.

The first subpixel electrode 191 h and the second subpixel electrode 191l are physically and electrically connected to the first drain electrode175 a and the second drain electrode 175 b through the contact holes 184a and 184 b, thereby receiving data voltages from the first drainelectrode 175 a and the second drain electrode 175 b. At this time, aportion of the data voltage applied to the second drain electrode 175 bis divided through the third source electrode 173 c, such that amagnitude of the voltage applied to the second subpixel electrode 191 lis less than the magnitude of the voltage applied to the first subpixelelectrode 191 h. Here, an area of the second subpixel electrode 191 lmay be approximately one to two times less than that of the firstsubpixel electrode 191 h.

A lower alignment layer (not shown) is formed on the pixel electrodes191. The lower alignment layer may be a vertical alignment layer, andmay be an alignment layer including a photo-reactive material. The photoreactive material will be described with reference to FIG. 44.

Next, the upper panel 200 will be described. The upper panel 200 of FIG.7 and FIG. 8 includes the color filter 230.

That is, the light blocking member 220 is positioned under theinsulation substrate 210. The light blocking member 220 is referred toas a “black matrix” and prevents light leakage. The light blockingmember 220 extends along the gate line 121, covers a region where thefirst thin film transistor (Qh), the second thin film transistor (Ql),and the third thin film transistor (Qc) are positioned, extends alongthe data line 171, and covers the surroundings of the data line 171. Aregion that is not covered by the light blocking member 220 emits lightto the outside, thereby displaying the images.

The color filter 230 is formed under the light blocking member 220. Thecolor filter 230 may display one of three primary colors such as red,green, and blue. Alternatively, each color filter 230 may display theprimary colors of yellow, cyan, magenta, and the like, or may display aplurality of colors other than these colors.

A planarization layer 250 providing a planar lower surface and made ofthe organic material is formed under the color filter 230.

A common electrode 270 made of the transparent conductive material isformed under the planarization layer 250.

An upper alignment layer (not shown) is formed under the commonelectrode 270. The upper alignment layer may be the vertical alignmentlayer, and may be an alignment layer in which a photo-polymer materialis photo-aligned.

Polarizers (not shown) are formed on the outer surface of the displaypanels 100 and 200, the polarization axes of the two polarizers arecrossed, and one polarization axis thereof may be parallel to the gatelines 121. However, the polarizer may only be disposed on one outersurface among the two display panels 100 and 200.

The liquid crystal layer 3 between the lower panel 100 and the upperpanel 200 includes liquid crystal molecules 31 having negativedielectric anisotropy.

The liquid crystal layer 3 or the alignment layer (not shown) mayfurther include the polymer that is polymerized by light, such asultraviolet rays. The polymer included in the liquid crystal layer 3provides the pretilt to the liquid crystal layer 3, and a method ofproviding the pretilt angle will be described in detail in FIG. 44. Thatis, the liquid crystal layer 3 may not include the polymer when thearrangement direction is sufficiently controlled without the polymerproviding the pretilt angle.

As described above, in the exemplary embodiment of FIG. 7 and FIG. 8,the step provider is the step providing wiring of the cross type formedwith the same layer as the gate line, thereby generating the step in theoverlying insulating layer/passivation layer.

FIG. 9 illustrates how the texture is reduced the most according to thethickness of the step providing wiring (referring to d of FIG. 8),thereby increasing the transmittance.

FIG. 9 is a view showing an experimental result using the exemplaryembodiment of FIG. 7 and FIG. 8.

In FIG. 9, “Plate only” means a case that the step providing wiring isnot formed, and “Gate” is an exemplary embodiment in which the stepproviding wiring is formed with the same layer as the gate line. Thatis, referring to FIG. 9, the texture is lowest in the case of the stepproviding wiring when the same layer as the gate line has a thickness of3000 Å compared to without the step providing wiring, and in the casethat the thickness of the step providing wiring is 6000 Å, the texturemay be further generated. Through the above experiment, when the stepproviding wiring with the same layer as the gate line has a thickness ofmore than 3000 Å and less than 4000 Å, the control force of the liquidcrystal molecules is improved such that the texture is reduced.

In the exemplary embodiment of FIG. 7 and FIG. 8, the step providingwiring is formed with the same layer as the gate line. However, the stepproviding wiring may be formed with the same layer as the data line asthe step provider. Also, the step providing wiring may be formed withthe same layer as the gate line and the data line, and this will bedescribed with reference to FIG. 10.

FIG. 10 is a layout view of a partial wiring part in a liquid crystaldisplay according to another exemplary embodiment of the presentinvention.

In (a) of FIG. 10, the step providing wiring is formed with the samelayer as the gate line, and (b) of FIG. 10 illustrates the stepproviding wiring being additionally formed with the same layer as thedata line, and the remaining structure is the same as the exemplaryembodiment of FIG. 6 and FIG. 7. That is, in FIG. 10, the pixelelectrode is not shown, however, similar to the structure of the pixelelectrode shown in FIG. 6 and FIG. 7, the pixel electrode 191 includesthe first subpixel electrode 191 h and the second subpixel electrode 192l, the first subpixel electrode 191 h includes the first partial plateelectrode 192 h and a plurality of first minute branch electrodes 193 h,and the second subpixel electrode 191 l includes the second partialplate electrode 192 l and a plurality of second minute branch electrodes193 l.

Among the step provider according to the exemplary embodiment of FIG.10, the first step providing wiring formed with the same layer as thegate line will be described with reference to (a) of FIG. 10.

In (a) of FIG. 10, gate line 121, the storage voltage line 131 and thefirst step providing wiring 132 h and 132 l are formed on the insulationsubstrate 110. The storage voltage line 131 includes storage electrodes135 a, 135 b, and 135 c, and a capacitor electrode 134 extendingdownward. The storage voltage line 131 includes two first longitudinalstorage electrode parts 135 a extending upward, a transverse storageelectrode part 135 b connecting the two first longitudinal storageelectrode parts 135 a, and two second longitudinal storage electrodeparts 135 c further extending upward from the transverse storageelectrode part 135 b. The first longitudinal storage electrode part 135a is formed along a longitudinal edge of the first sub-pixel electrode191 h formed thereon, and the second longitudinal storage electrode part135 c is formed along the longitudinal edge of the second sub-pixelelectrode 191 l formed thereon. Meanwhile, the transverse storageelectrode part 135 b is positioned between a transverse edge of theprevious second sub-pixel electrode 191 l and the transverse edge of thecurrent first sub-pixel electrode 191 h, and is formed along the twotransverse edges. The first longitudinal storage electrode part 135 aand the transverse storage electrode part 135 b are formed along theedge of the first sub-pixel electrode 191 h, thereby at least partiallyoverlapping the first sub-pixel electrode 191 h, and the secondlongitudinal storage electrode part 135 c and the transverse storageelectrode part 135 b are formed along the edge of the second sub-pixelelectrode 191 l, thereby at least partially overlapping the secondsub-pixel electrode 191 l. In FIG. 1, the overlying transverse storageelectrode part 135 b and the underlying transverse storage electrodepart 135 b appear to be separated from each other, but in actuality, thetransverse storage electrode parts 135 b of the pixels PX that areadjacent up and down are electrically connected to each other.

The first step providing wiring 132 h and 132 l is formed with the samelayer and the same material as the gate line 121 and the storage voltageline 131, and in the exemplary embodiment of FIG. 10, is electricallyconnected to the storage electrodes 135 a, 135 b, and 135 c of thestorage voltage line 131. That is, the first-first step providing wiring132 h has the straight shape extending in the longitudinal direction,and two ends are respectively connected to the transverse storageelectrode part 135 b and the storage voltage line 131. The first-secondstep providing wiring 132 l has the straight shape extending in thelongitudinal direction, and two ends are connected to the transversestorage electrode part 135 b.

The gate insulating layer is formed on the gate line 121, the storagevoltage line 131, and the first step providing wiring 132 h and 132 l,and the semiconductor layer and the ohmic contact layer are formedthereon.

As shown in (b) of FIG. 10, second step providing wires 172 h, 172′h,172 l, and 172′l are additionally formed with the same layer as the dataline. Among the second step providing wires 172 h, 172′h, 172 l, and172′l, the second-first step providing wires 172 h and 172 l have thestraight shape extending in the longitudinal direction and overlap thefirst step providing wires 132 h and 132 l. Meanwhile, the second-secondstep providing wires 172′h and 172′l have the straight shape extendingin the transverse direction, and the second-first step providing wires172 h and 172 l are connected, thereby forming a cross shape.

The exemplary embodiment of FIG. 10 has the following advantages.

Referring to FIG. 9, the step providing wiring must be formed with athickness of more than about 3000 Å to less than 4000 Å. However, it isdifficult to form the above thickness with a single layer. In this case,as shown in FIG. 10(a) and FIG. 10(b), one step providing wire is formedwith the same material as the gate line, and one step providing wireformed with the same material as the data line is formed thereon,thereby providing the sufficient step.

As opposed to the exemplary embodiment of FIG. 10, the first stepproviding wiring formed with the same layer as the gate line may have across shape, and in this case, one end of the first step providingwiring may be connected to the storage electrodes 135 a, 135 b, and 135c.

The passivation layer formed of the inorganic material is formed on thedata line and the second step providing wires 172 h, 172′h, 172 l, and172′l, and the wiring providing step part is formed in the passivationlayer by the first and second step providing wiring.

In FIG. 10, the pixel electrode is not shown. However, referring to FIG.7 and FIG. 8, the first partial plate electrode 192 h covers the firstwiring providing step part generated in the passivation layer 180 by thefirst and second step providing wires 132 h, 172 h, and 172′h. As aresult, the first partial plate electrode 192 h has the step provided bythe first wiring providing step part of the passivation layer 180. Also,the second partial plate electrode 192 l covers the second wiringproviding step part generated in the passivation layer 180 by the firstand second step providing wires 132 l, 172 l, and 172′l. As a result,the second partial plate electrode 192 l has the step provided by thesecond wiring providing step part of the passivation layer 180.

Here, the first and second wiring providing step part provides thepretilt to the liquid crystal molecules, thereby controlling anarrangement direction of the liquid crystal molecules, and as a result,texture is reduced.

In the exemplary embodiment of FIG. 4, FIG. 5, FIG. 7, and FIG. 8, thevarious exemplary embodiments of the step provider shown in FIG. 1 andFIG. 2 have been described.

In FIG. 11 to FIG. 16, similar to the step provider of FIG. 1 and FIG.2, the step providing groove and the cross-shaped protrusion are formedin the passivation layer 180 of the insulator, and variations of thestep providing groove and a manufacturing method thereof will bedescribed.

FIG. 11, (b) of 12, and 14 are cross-sectional views of a liquid crystaldisplay according to another exemplary embodiment of the presentinvention, and FIGS. 13, 15, and 16 illustrate masks used formanufacturing the same.

Firstly, an exemplary embodiment having a taper structure in a side wallin a step providing groove 185 formed in the passivation layer 180 ofthe insulator will be described with reference to FIG. 11 to FIG. 13.

FIG. 11 corresponds to FIG. 2, and is the same as FIG. 2 except for apoint where the side wall of the step providing groove 185 has a taperstructure (referring to “T”) and is inclined. As shown in the layoutview, the taper structure is indicated by T in (a) of FIG. 12. As shownin (a) of FIG. 12, the tapered region is formed in the slanted sidesurface of the step providing groove 185 corresponding to each edge ofthe partial plate electrode. Also, in the layout view, the stepproviding groove 185 is a right triangle, and the side surfacecorresponding to the oblique edge in the layout view has a slanted taperstructure.

Meanwhile, in the exemplary embodiment of FIG. 11, the cross-shapedprotrusion 182 formed in the passivation layer 180 of the insulator doesnot have the taper structure. However, according to an exemplaryembodiment, as shown in (b) of FIG. 12, the cross-shaped protrusion 182may also have the taper structure.

In (c) of FIG. 12 as the drawing for testing the texture generation andthe transmittance of the pixel having the structure of FIG. 11 and (a)of FIG. 12, it may be confirmed that the control force of the liquidcrystal molecules is improved in the side wall of the step providinggroove 185 formed with the taper structure such that the texture isdecreased compared with the other side walls of the step providinggroove 185.

As shown in FIG. 11 and (a) of FIG. 12, to form the taper structure atthe side wall of the step providing groove 185, a slit mask shown inFIG. 13 may be used for exposure and developing.

In FIG. 13, a slit mask is positioned at the side wall where the taperstructure will be formed in the step providing groove 185, and theexposure process is executed such that the taper structure is formed bythe difference of the exposure amount. In the slit mask used in thepresent exemplary embodiment of the present invention, a bar blockinglight and an opening part transmitting light are repeated 2-4 times, andthe width of the bar and the opening part has a value of more than 0.8to less than 2 μm.

According to an exemplary embodiment of the present invention, thetapered side wall may be formed without the slit mask shown in FIG. 13.This is the because the side wall does not have the completely verticalstructure and the tapered structure is formed when forming the patternthrough the general exposure/developing such that the step providinggroove 185 having the slightly tapered side wall may be formed withoutthe separate slit mask.

The case of using the slit mask as shown in FIG. 13 may be applied whenforming a larger taper angle than the general etching.

On the other hand, FIG. 14 to FIG. 16 show an exemplary embodiment inwhich a lower surface (a bottom surface) of the step providing groove185 formed in the passivation layer 180 of the insulator is slanteddifferently than as shown in FIG. 11 to FIG. 13.

In FIG. 14 corresponding to FIG. 2, the lower surface (the bottomsurface) of the step providing groove 185 is completely inclined, whilethe lower surface and one side surface are integrally formed with apredetermined slope. That is, in the exemplary embodiment of FIG. 14,the tapered region is wider than in the exemplary embodiment of FIG. 11such that the “B” region of FIG. 14 has an overall tapered structure.

As shown in FIG. 14, to form the entire inclination structure on thelower surface, a mask such as the slit mask controlling the exposureamount must be used, and the usable mask is respectively shown in FIG.15 and FIG. 16.

First, the mask of FIG. 15 as the slit mask is positioned through theoverall step of providing the groove 185 formed in the passivation layer180 of the insulator and then the exposure is executed, and the slitmask includes the bar blocking the light and the opening part passingthe light that are repeated and has a structure in which the width ofthe opening part is gradually increased. Here, the width of the bar hasa value of more than 0.8 to less than 2 μm, and the width of the openingpart is continuously increased from the width more than 0.8 to less than2 μm to a value of more than 0.2 to less than 0.5 μm.

If the step providing groove 185 is formed by using this slit mask asshown in FIG. 15, the step providing groove 185 has a structure in whichthe depth of the cross-section is uniformly changed.

On the other hand, a slit mask of FIG. 16 has a structure including agroup having the opening part of the same interval, as opposed to theshown in FIG. 15, and a group a1, a group a2, a group a3, and a group a4are shown in FIG. 16. That is, the width of the bar in all groups has anequal value of more than 0.8 to less than 2 although each group has adifferent interval of the opening part. However, the interval of groupa2 is greater than group a1, and the interval of the opening part isincreased to be closer to group a2, group a3, and group a4.

When exposing by using the slit mask shown in FIG. 16, a step providinggroove 185 having a step-shaped like the cross-section shown in FIG. 16may be formed. The real pattern has the rounded step shape compared withthe cross-section shown in FIG. 16, thereby having the cross-sectionalstructure in which the width is gradually changed.

The step providing groove 185 formed by using the slit mask shown inFIG. 15 and FIG. 16 improves the control force of the liquid crystalmolecules as a result of the step in the step providing groove 185,thereby reducing the generation of the texture. Also, the step providinggroove 185 reinforces the control force of the liquid crystal moleculesmore than any other exemplary embodiment, as shown in FIG. 44. Althoughthe liquid crystal layer or the alignment layer does not include thepretilt providing polymer that is polymerized by light such asultraviolet rays, the liquid crystal molecules may be sufficientlycontrolled and the texture may be prevented.

The exemplary embodiment of the present invention that does not includethe pretilt providing polymer that is polymerized by light, such asultraviolet rays, will be described with reference to FIG. 17 to FIG.19.

FIG. 17 is a layout view of a liquid crystal display according toanother exemplary embodiment of the present invention, and FIG. 18 is across-sectional view taken along the line XVIII-XVIII of FIG. 17.

Referring to FIG. 17 and FIG. 18, the liquid crystal display accordingto the present exemplary embodiment includes the lower panel 100 and theupper panel 200 facing each other, the liquid crystal layer 3 interposedbetween the two display panels 100 and 200, and a pair of polarizers(not shown) attached at the outer surfaces of the display panels 100 and200.

The lower panel 100 will now be described.

The gate line 121 and the storage voltage line 131 are formed on aninsulation substrate 110. The gate line 121 includes a first gateelectrode 124 a, a second gate electrode 124 b, and a third gateelectrode 124 c. The storage voltage line 131 includes storageelectrodes 135 a, 135 b, and 135 c, and a capacitor electrode 134extending downward. The storage voltage line 131 includes two firstlongitudinal storage electrode parts 135 a extending upward, atransverse storage electrode part 135 b connecting the two firstlongitudinal storage electrode parts 135 a, and two second longitudinalstorage electrode parts 135 c further extending upward from thetransverse storage electrode part 135 b.

The first longitudinal storage electrode part 135 a is formed along alongitudinal edge of the first sub-pixel electrode 191 h formed thereon,and the second longitudinal storage electrode part 135 c is formed alongthe longitudinal edge of the second sub-pixel electrode 191 l formedthereon. Meanwhile, the transverse storage electrode part 135 b ispositioned between a transverse edge of the previous second sub-pixelelectrode 191 l and the transverse edge of the current first sub-pixelelectrode 191 h, and is formed along the two transverse edges.

As a result, the first longitudinal storage electrode part 135 a and thetransverse storage electrode part 135 b are formed along the edge of thefirst sub-pixel electrode 191 h, thereby at least partially overlappingthe first sub-pixel electrode 191 h, and the second longitudinal storageelectrode part 135 c and the transverse storage electrode part 135 b areformed along the edge of the second sub-pixel electrode 191 l, therebyat least partially overlapping the second sub-pixel electrode 191 l.

In FIG. 17, the overlying transverse storage electrode part 135 b andthe underlying transverse storage electrode part 135 b appear to beseparated from each other, but in actuality, the transverse storageelectrode parts 135 b of the pixels PX that are adjacent up and down areelectrically connected to each other.

The gate insulating layer 140 is formed on the gate line 121 and thestorage voltage line 131. The first semiconductor 154 a, the secondsemiconductor 154 b, and the third semiconductor 154 c are formed on thegate insulating layer 140.

The plurality of ohmic contacts (not shown) are formed on the firstsemiconductor 154 a, the second semiconductor 154 b, and the thirdsemiconductor 154 c.

Data conductors 171, 173 c, 175 a, 175 b, and 175 c including aplurality of data lines 171 which include the first source electrode 173a and the second source electrode 173 b, the first drain electrode 175a, the second drain electrode 175 b, the third source electrode 173 c,and the third drain electrode 175 c, are formed on the semiconductor(the first semiconductor 154 a, the second semiconductor 154 b, and thethird semiconductor 154 c), the ohmic contacts (not shown), and the gateinsulating layer 140.

The first gate electrode 124 a, the first source electrode 173 a, andthe first drain electrode 175 a form a first thin film transistor Qatogether with the first semiconductor 154 a, and a channel of the firstthin film transistor Qa is formed in the semiconductor portion 154 abetween the first source electrode 173 a and the first drain electrode175 a. Similarly, the second gate electrode 124 b, the second sourceelectrode 173 b, and the second drain electrode 175 b form a second thinfilm transistor Qb together with the second semiconductor 154 b, achannel of the second thin film transistor Qb is formed in thesemiconductor portion 154 b between the second source electrode 173 band the second drain electrode 175 b, the third gate electrode 124 c,the third source electrode 173 c, and the third drain electrode 175 cform a third thin film transistor Qc together with the thirdsemiconductor 154 c, and a channel of the third thin film transistor Qcis formed in the semiconductor portion 154 c between the third sourceelectrode 173 c and the third drain electrode 175 c.

The passivation layer 180 is formed on the gate insulating layer 140,the data conductors 171, 173 c, 175 a, 175 b, and 175 c, and the exposedportion of the semiconductors 154 a, 154 b, and 154 c. The passivationlayer 180 may be formed of an insulator such as silicon nitride andsilicon oxide, or an insulator, and in the exemplary embodiment of FIG.17, the organic insulating layer including the insulator is described.

The step provider providing the step to the overlying layer is formed inthe passivation layer 180 of the insulator, and in FIG. 17, the stepproviding grooves 185 h and 185 l and the protrusion 182 of the crosstype positioned between the step providing grooves 185 h and 185 l arethe step provider. As shown in FIG. 17, the step providing grooves 185 hand 185 l have a quadrangle structure having two edges crossingperpendicularly and are symmetrical to each other in the diagonaldirection. As a result, the passivation layer 180 includes thecross-shaped protrusion 182.

Also, referring to FIG. 18, the lower surface of the step providinggrooves 185 h and 185 l are entirely inclined, while forming thepredetermined slope by the lower surface and one side surface that areintegral. As described above, the lower surface of the step providinggrooves 185 h and 185 l has a slope such that the alignment direction ofthe liquid crystal molecules is controlled, thereby reducing thegeneration of the texture.

The passivation layer 180 includes the first contact hole 184 a, thesecond contact hole 184 b, and the third contact hole 184 c respectivelyexposing the first drain electrode 175 a, the second drain electrode 175b, and the third drain electrode 175 c. The passivation layer 180includes the opening 189 collecting the gas emitted from the colorfilter 230. According to FIG. 17, one pixel may include a pair ofopenings 189.

The pixel electrode 191, including the first sub-pixel electrode 191 hand the second sub-pixel electrode 191 l, is formed on the passivationlayer 180. The first sub-pixel electrode 191 h and the second sub-pixelelectrode 191 l respectively include partial plate electrodes 192 h and192 l positioned at a center thereof and a plurality of minute branchelectrodes 193 h and 193 l protruding from the partial plate electrode192 h and 192 l in an oblique direction.

The first sub-pixel electrode 191 h includes the first partial plateelectrode 192 h and a plurality of first minute branch electrodes 193 hpositioned in the square region, and is connected to a wide end portionof the first drain electrode 175 a by the first minute branch connection194 h extending outside the square region.

The first partial plate electrode 192 h has an equilateral octagonalshape, the center thereof is positioned at the center of the squareregion, and four vertices of the equilateral octagonal shape meet theboundary of the square region. The first partial plate electrode 192 hcovers the first step providing groove 185 h of the passivation layer180 and the first cross-shaped protrusion 182 h. As a result, the firstpartial plate electrode 192 h has the step provided by the first stepproviding groove 185 h of the passivation layer 180 and the firstcross-shaped protrusion 182 h. Here, referring to FIG. 18, the firstcross-shaped protrusion 182 h provides a pretilt to the liquid crystalmolecules at the center of the square region, thereby controlling anarrangement direction of the liquid crystal molecules, and as a result,texture is reduced.

A plurality of first minute branch electrodes 193 h are extended ineight edges of the oblique direction of the first partial plateelectrode 192 h. A plurality of first minute branch electrodes 193 hfill the rest of the square region, form an angle of 45 degrees withrespect to the gate line 121 or the data line 171, and form an angle of90 degrees with respect to the edge of the oblique direction of thefirst partial plate electrode 192 h.

In the exemplary embodiment of FIG. 17, the first sub-pixel electrode191 h includes the first minute branch connection 194 h connecting thefirst partial plate electrode 192 h and the ends of a plurality of firstminute branch electrodes 193 h in a longitudinal direction or ahorizontal direction. The first minute branch connection 194 h overlapsthe first sub-pixel electrode 191 h and the underlying storageelectrodes 135 a and 135 b, thereby forming a storage capacitance.However, according to an exemplary embodiment, the first connection 194h may be omitted, and in this case, a plurality of first minute branchelectrodes 193 h protrude to the outside.

The second sub-pixel electrode 191 l includes the second partial plateelectrode 192 l and a plurality of second minute branch electrodes 193 lformed in the rectangle region having a longitudinal edge, and isconnected to the wide end portion of the second drain electrode 175 l bythe second connection 197 l extending outside the rectangle region.

The center of the second partial plate electrode 192 l is positioned atthe center of the rectangle region and has an octagonal shape connectingthe center of each edge of the rectangle region. As a result, fourvertices of the octagon meet the boundary of the rectangle region. Thesecond partial plate electrode 192 l covers the second step providinggroove 185 l of the passivation layer 180 and the second cross-shapedprotrusion 182 l. As a result, the second partial plate electrode 192 lhas the step provided by the second step providing groove 185 l of thepassivation layer 180 and the second cross-shaped protrusion 182 l.(referring to FIG. 18)

A plurality of second minute branch electrodes 193 l extend from eightedges of the oblique direction of the second partial plate electrode 192l. A plurality of second minute branch electrodes 193 l fill the rest ofthe rectangle region, form an angle of 45 degrees with respect to thegate line 121 or the data line 171, and form an angle of 90±15 degreeswith respect to the edge of the oblique direction of the second partialplate electrode 192 l.

In the exemplary embodiment of FIG. 17, the second sub-pixel electrode191 l includes the second minute branch connection 194 l connecting thesecond partial plate electrode 192 l and the ends of a plurality ofsecond minute branch electrodes 193 l in a longitudinal direction or ahorizontal direction. The second minute branch connection 194 l overlapsthe second sub-pixel electrode 191 l and the underlying storageelectrodes 135 b and 135 c, thereby forming a storage capacitance.However, according to an exemplary embodiment, the second minute branchconnection 194 l may be omitted, and in this case, a plurality of secondminute branch electrodes 193 l protrude to the outside.

The first sub-pixel electrode 191 h and the second sub-pixel electrode191 l are physically and electrically connected to the first drainelectrode 175 a and the second drain electrode 175 b through the contactholes 184 a and 184 b, thereby receiving data voltages from the firstdrain electrode 175 a and the second drain electrode 175 b. At thistime, the portion of the data voltage applied to the second drainelectrode 175 b is divided through the third source electrode 173 c,such that a magnitude of the voltage applied to the second sub-pixelelectrode 191 l is less than the magnitude of the voltage applied to thefirst sub-pixel electrode 191 h. Here, an area of the second sub-pixelelectrode 191 l may be approximately one to two times less than that ofthe first sub-pixel electrode 191 h.

The storage electrode connecting member 139 connects the capacitorelectrode 134 of the storage voltage line 131 and the third drainelectrode 175 c through the contact hole 184 c. A storage voltage Vcstis applied to the capacitor electrode 134 of the storage voltage line131 to have a predetermined voltage, and thereby apply the storagevoltage Vcst to the third thin film transistor Qc through the thirddrain electrode 175 c. As a result, the voltage applied to the secondsub-pixel may be decreased.

The cover 199 covering the opening 189 of the passivation layer 180 isformed on the opening 189. According to FIG. 17, one pixel may include apair of covers 199. The pixel electrode 191 and the cover 199 may bemade of the transparent conductive material such as ITO or IZO.According to an exemplary embodiment of the present invention, theopening 189 and the cover 199 may be omitted.

The lower alignment layer (not shown) is formed on the pixel electrodes191. The lower alignment layer may be a vertical alignment layer. Thelower alignment layer does not include the photo-reactive material shownin FIG. 44. This is because the exemplary embodiment of FIG. 17 hassufficient control force of the liquid crystal molecules.

The common electrode panel 200 will now be described. The upper panel200 of FIG. 17 and FIG. 18 includes the color filter 230.

The light blocking member 220 is formed on an insulation substrate 210.The light blocking member 220 is referred to as black matrix, andprevents light leakage. The light blocking member 220 extends along thegate line 121, covers a region where the first thin film transistor(Qh), the second thin film transistor (Ql), and the third thin filmtransistor (Qc) are positioned, extends along the data line 171, andcovers the surroundings of the data line 171. The region that is notcovered by the light blocking member 220 emits light to the outside,thereby displaying the images.

The color filter 230 is formed under the light blocking member 220. Thecolor filter 230 may display one of three primary colors such as red,green, and blue, but it is not limited to display of the three primarycolors and may display one of cyan, magenta, yellow, and white-basedcolors.

A planarization layer 250 providing a planar lower surface and made ofthe organic material may be formed under the color filter 230.

A common electrode 270 made of the transparent conductive material maybe formed under the planarization layer 250.

The upper alignment layer (not shown) is formed under the commonelectrode 270. The upper alignment layer may be a vertical alignmentlayer. The upper alignment layer does not include the photo-reactivematerial shown in FIG. 44. This is because the exemplary embodiment ofFIG. 17 has sufficient control force of the liquid crystal molecules.

Polarizers (not shown) are formed on the outer surface of the displaypanels 100 and 200, the polarization axis of the two polarizers arecrossed, and one polarization axis thereof may be parallel to the gatelines 121. The polarizer may be disposed on one outer surface among thetwo display panels 100 and 200.

The first sub-pixel electrode 191 h and the second sub-pixel electrode191 l to which the data voltage is applied generate an electric field inconjunction with the common electrode 270 of the common electrode panel200 such that the liquid crystal molecules of the liquid crystal layer 3that are aligned vertical to the surface of the two electrodes 191 and270 in the absence of an electric field are slanted in the directionparallel to the surface of the two electrodes 191 and 270, and therebythe luminance of the light transmitted through the liquid crystal layer3 differs depending on the slant degree of the liquid crystal molecules.

The liquid crystal display may further include a spacer to maintain acell interval between the two display panels 100 and 200, and the spacermay be attached to the upper panel 200 or the lower panel 100.

The liquid crystal layer 3 disposed between the lower panel 100 and theupper panel 200 includes the liquid crystal molecules 31 having negativedielectric anisotropy. The liquid crystal layer 3 does not include thephoto-reactive material shown in FIG. 44. This is because the exemplaryembodiment of FIG. 17 has sufficient control force of the liquid crystalmolecules.

As described above, in the exemplary embodiment of FIG. 17 and FIG. 18,the step provider is formed in the passivation layer 180 of theinsulator and made of the cross-type protrusions 182 h and 182 lpositioned between the step providing grooves 185 h and 185 l. Thepartial plate electrodes 192 h and 192 l have an octagonal shape.

The lower surface of the step providing grooves 185 h and 185 l istotally inclined, while forming the predetermined slope by the lowersurface and one integral side surface. As described above, the lowersurface of the step providing grooves 185 h and 185 l is inclined suchthat the alignment direction of the liquid crystal molecules iscontrolled, thereby providing the pretilt. The step providing grooves185 h and 185 l of FIG. 17 are formed at a wider region than anotherexemplary embodiment such that the region providing the pretilt to theliquid crystal molecule is widened. As a result, the liquid crystalmolecules are not misaligned, and the texture is not generated. Becausethe texture is not generated in the embodiment of FIG. 17, thephoto-reactive material shown in FIG. 44 may not be included.

Next, a characteristic of the exemplary embodiment of FIG. 17 and FIG.18 will be described focusing on an experimental result for theexemplary embodiment of FIG. 17 and FIG. 18.

FIG. 19 is a view showing an experimental result using the exemplaryembodiment of FIG. 17 and FIG. 18.

First, (a) of FIG. 19 is an experimental result of the exemplaryembodiment in which the partial plate electrode has a rhombus structure,the step providing groove has a lower surface that is entirely inclined,and the photo-reactive material is not inclined in the liquid crystallayer or the alignment layer. As shown in (a) of FIG. 19, the texture isgenerated in the portion of the minute branch electrode. This is becausethe photo-reactive material does not exist on the minute branchelectrode such that the liquid crystal molecules do not have thepretilt.

(b) of FIG. 19 is an experimental result using the exemplary embodimentof FIG. 17 and FIG. 18. The partial plate electrode has an octagonalstructure such that the region forming the minute branch electrodes isreduced, and as a result, although the photo-reactive material does notexist, the liquid crystal molecules are controlled with the pretiltprovided by the inclined lower surface in the step providing groove suchthat the texture may not be generated.

In FIG. 19, (c) clearly shows the direction of the pretilt provided fromthe lower surface of the step providing groove and the pretilt providedto the liquid crystal molecules as a result of the cross-shapedprotrusion. That is, in the cross-sectional view of (c) of FIG. 19, theliquid crystal molecule has the pretilt according to the slope of thelower surface of the step providing groove, and in the plane view of (c)of FIG. 19, the pretilt direction of the liquid crystal molecules isshown through arrows 1, 2, and 3. In the plane view of (c) of FIG. 19,the arrow 1 indicates the pretilt direction generated by the inclinedslope in the side wall portion of the step providing groove. In theplane view of (c) of FIG. 19, the arrow 2 indicates the pretiltdirection generated by the inclined slope in the lower surface of thestep providing groove. In the plane view of (c) of FIG. 19, the arrow 3indicates the pretilt direction generated by the cross-type protrusion.

As described above, in the exemplary embodiment of FIG. 17 and FIG. 18,although the photo-reactive material is not formed in the liquid crystallayer or the alignment layer, the alignment direction of the liquidcrystal molecules may be sufficiently controlled in three large pretiltdirections such that the texture is not generated.

Next, various structures of the pixel electrode will be described withreference to FIG. 20 to FIG. 24.

FIG. 20 to FIG. 24 are enlarged views of a pixel electrode of a liquidcrystal display according to another exemplary embodiment of the presentinvention.

Firstly, FIG. 20 shows a structure of the pixel electrode including an“X” shaped partial plate electrode and an experimental result oftransmittance. FIG. 20 shows the structure corresponding to the firstsub-pixel electrode of FIG. 1.

The pixel electrode according to the exemplary embodiment of FIG. 20includes an “X” shaped partial plate electrode 192 and the minute branchelectrodes 193 extended therefrom.

In the “X” shaped partial plate electrode 192, a transverse extensionand a longitudinal extension traversing the pixel area in thelongitudinal direction and the transverse direction are formed.

The “x” shaped partial plate electrode 192 has four portions forming theX shape, and each portion has a structure in which the width isgradually decreased from the center of the pixel electrode to the outerpart.

Each portion has a triangular shape having the center of the pixel, onecorner of the pixel, and the position on the center of the pixel and thetransverse extension as the vertices.

In the “X” shaped partial plate electrode 192, the transverse extension,the longitudinal extension, and minute branch electrodes 193 areextended and formed in the rest of the portion of the pixel area, andare arranged parallel to the edge of the adjacent portion.

In the exemplary embodiment of FIG. 20, a minute branch connectionenclosing the outer part of the pixel area is further included. Theminute branch connection is formed at four edges of the pixel area.However, according to an exemplary embodiment, it may be formed at atleast one edge or may not be formed at all.

The pixel according to the exemplary embodiment of FIG. 20 includes astep provider H. FIG. 20 schematically shows the step provider Hproviding the step to the corresponding region as one of theabove-described drawings.

Referring to the transmittance of the exemplary embodiment of FIG. 20,the texture is partially generated according to the edge of the “X”shaped partial plate electrode 192 such that it may be confirmed thatthe texture of the “X” shape is generated.

FIG. 21 shows an exemplary embodiment having the partial plate electrodehaving two rectangle structures in one pixel area. FIG. 21 shows astructure corresponding to the first sub-pixel electrode of FIG. 1.

The pixel electrode of the exemplary embodiment of FIG. 21 includes thepartial plate electrode 192 having two rectangle structures and theminute branch electrodes 193 extending therefrom.

The pixel electrode includes the transverse extension and thelongitudinal extension crossing the pixel area, and the transverseextension crossing the partial plate electrode of two rectanglestructures.

The partial plate electrode 192 has two rectangle structures, and onerectangle structure is formed parallel to the longitudinal extension.

In the partial plate electrode 192, the transverse extension, thelongitudinal extension, and the minute branch electrodes 193 extend andare formed in the rest of the pixel area, while forming an angle of, forexample, 45 degrees with respect to one edge of the partial plateelectrode.

The exemplary embodiment of FIG. 21 further includes the minute branchconnection enclosing the outer part of the pixel area. The minute branchconnection is formed at four edges of the pixel area. However, accordingto an exemplary embodiment, it may be formed at at least one edge or maynot be formed at all.

The pixel according to the exemplary embodiment of FIG. 21 includes thestep provider H. FIG. 21 schematically shows the step provider Hproviding the step to the corresponding region as one of theabove-described drawings.

Referring to the transmittance of the exemplary embodiment of FIG. 21,the texture is weakly generated according to the edge of the partialplate electrode 192 of the rectangle.

FIG. 22 shows the structure of the pixel electrode according to anexemplary embodiment of the present invention.

In FIG. 22, (a) and (b) show the structure corresponding to the secondsub-pixel electrode of FIG. 1, and (c) of FIG. 22 shows the structurecorresponding to the first sub-pixel electrode of FIG. 1.

Referring to (a) and (b) of FIG., (a) of FIG. 22 shows a case of formingone partial plate electrode 192 l in the region of the second sub-pixelelectrode, and (b) of FIG. 22 shows the structure in which two partialplate electrodes 192 l are connected up and down in the region of thesecond sub-pixel electrode. Particularly, the second sub-pixel electrodeis formed in the rectangle region, and when bisecting the rectangleregion up and down, each region is a square region. In each squareregion, one partial plate electrode having a rhombus structure isformed.

In other regions, the longitudinal extension (referring to (a) of FIG.22) or the transverse extension (not shown) may be formed, and theminute branch electrodes are formed in the rest of the region.

Referring to (a) of FIG. 22, the partial plate electrode 192 l contactsat least one position of the side surfaces of the second sub-pixelelectrode, and two positions in (a) of FIG. 22.

In (c) of FIG. 22, the partial plate electrode 192 h has a circularstructure. FIG. 22 shows only the structure corresponding to the firstsub-pixel electrode, however, according to an exemplary embodiment, thepartial plate electrode may be formed in the second sub-pixel electrodethereby having an oval structure, like (b) of FIG. 22, where the partialplate electrode of two circuital structures may be formed. The minutebranch electrodes may be formed outside of the partial plate electrode192 h of the circular structure.

Referring to (c) of FIG. 22 and the structure of the previous partialplate electrodes, the partial plate electrode according to an exemplaryembodiment of the present invention may have a polygon shape such as aquadrangular shape of a rhombus, an octagonal shape, or a circularshape.

FIG. 23 and FIG. 24 show the pixel electrode structure according to anexemplary embodiment of the present invention, and the structure of thepixel electrode shown in FIG. 23 and FIG. 24 further improves thelateral visibility.

That is, the partial plate electrodes 192 h and 192 l shown in FIG. 23have a structure in which the width in the horizontal direction isgreater than the width in the vertical direction. In this case, a headdirection of the liquid crystal molecules is slanted to the side, and asa result, the lateral visibility is improved in the direction of viewingof the head direction of the corresponding liquid crystal molecules.That is, in another exemplary embodiment, the liquid crystal moleculesare arranged in the direction of a 45 angle, however, in the exemplaryembodiment of FIG. 23, the liquid crystal molecules are arranged at asmaller angle such that the viewing angle characteristic is improved inthe side. Referring to FIG. 24, in the partial plate electrode structurehaving the large width of the horizontal direction like FIG. 23, thealignment direction of the liquid crystal molecules is shown to bearranged at an angle of less than 45 degrees. This is in reference tothe region indicated by a dotted line of FIG. 24.

The above-described exemplary embodiment of the present invention isapplied to various pixel structures, and representative examples appliedwith each pixel structure will be described with reference to FIG. 25 toFIG. 32.

First, referring to FIG. 25 and FIG. 26, a structure in which twosub-pixels are coupled by the storage capacitor Cas after receiving thedata voltage from one transistor Q will be described.

FIG. 25 is an equivalent circuit diagram of one pixel of a liquidcrystal display according to another exemplary embodiment of the presentinvention, and FIG. 26 is a layout view of a lower panel of a liquidcrystal display according to another exemplary embodiment of the presentinvention.

The liquid crystal display according to an exemplary embodiment of thepresent invention includes signal lines including a plurality of gatelines GL, a plurality of data lines DL, and a plurality of storagevoltage lines SL and a plurality of pixels PX connected thereto. Eachpixel PX includes a pair of a first sub-pixel PXa and a second sub-pixelPXb, wherein the first sub-pixel PXa includes the first sub-pixelelectrode (191 h of FIG. 26), and the second sub-pixel PXb includes thesecond sub-pixel electrode (191 l of FIG. 26).

The liquid crystal display according to an exemplary embodiment of thepresent invention further includes the switching element Q connected tothe gate line GL and the data line DL, the first liquid crystalcapacitor Clca and the first storage capacitor Csta that are connectedto the switching element Q and formed in the first sub-pixel PXa, thesecond liquid crystal capacitor Clcb and the second storage capacitorCstb that are connected to the switching element Q and formed in thesecond sub-pixel PXb, and an assistance capacitor Cas formed between theswitching element Q and the second liquid crystal capacitor Clcb.

The switching element Q is a three-terminal element, such as a thin filmtransistor, disposed at the lower panel 100. The switching element Qincludes a control terminal connected to a gate line (GL), an inputterminal connected to a data line (DL), and an output terminal connectedto the first liquid crystal capacitor Clca, the storage capacitor Csta,and the assistance capacitor Cas.

One terminal of the assistance capacitor Cas is connected to the outputterminal of the switching element Q, and the other terminal is connectedto the second liquid crystal capacitor Clcb and the second storagecapacitor Cstb.

The charging voltage of the second liquid crystal capacitor Clcb islower than the charging voltage of the first liquid crystal capacitorClca by the assistance capacitor Cas such that the lateral visibility ofthe liquid crystal display may be improved.

In the structure of the liquid crystal display according to an exemplaryembodiment of the present invention, as shown in FIG. 26, a plurality ofgate conductors including a plurality of gate lines 121 and a pluralityof storage voltage lines 131 are formed on the insulation substrate (notshown) made of transparent glass or plastic.

The gate line 121 transmits gate signals and extends in a substantiallyhorizontal direction. Each gate line 121 includes a plurality of gateelectrodes 124 protruding upward.

The storage electrode line 131 receives a predetermined voltage, and mayextend parallel to the gate line 121. Each storage voltage line 131 ispositioned between two adjacent gate lines 121. The storage voltage line131 includes the storage electrodes 135 a and 135 b extending downward.However, the shape and the arrangement of the storage voltage lines 131and the storage electrodes 135 a and 135 b may be variously changed.

The gate insulating layer (not shown) is formed on the gate conductors121 and 131. A semiconductor island 154 is formed on the gate insulatinglayer. The semiconductor island 154 is positioned on the gate electrode124.

The data conductor including a plurality of data lines 171 and drainelectrodes 175 is formed on the semiconductor 154 and the gateinsulating layer.

The data lines 171 transmit the data signals and extend in the verticaldirection thereby intersecting the gate lines 121 and the storagevoltage lines 131. Each data line 171 includes a source electrode 173which extends toward the gate electrode 124.

The drain electrode 175 is separated from the data line 171 and includesa bar-shaped end facing the source electrode 173 with respect to thegate electrode 124. The bar-shaped end is partially surrounded by thesource electrode 173 which is curved.

The other end of the drain electrode 175 substantially extends parallelto the data line 171 thereby being formed through the first sub-pixelPXa and the second sub-pixel PXb, and the portion formed in the secondsub-pixel PXb is referred to as an auxiliary electrode 176.

The passivation layer (not shown) is formed on the data conductors 171and 175 and the semiconductor 154. The passivation layer may be made ofan insulator and has a flat surface. The step provider providing thestep to the overlying layer is formed in the passivation layer of theinsulator, and in FIG. 26, the step providing grooves 185 h and 185 land the cross-shaped protrusions 182 h and 182 l positioned between thestep providing grooves 185 h and 185 l are the step provider. As shownin FIG. 26, the step providing grooves 185 h and 185 l have a righttriangle structure and are symmetrical to each other in a diagonaldirection. As a result, the passivation layer 180 includes thecross-shaped protrusions 182 h and 182 l.

The color filter may be formed under the passivation layer.

A plurality of pixel electrodes 191 are formed on the passivation layer.Each pixel electrode 191 includes the first sub-pixel electrode 191 hand the second sub-pixel electrode 191 l formed at predeterminedintervals.

The first sub-pixel electrode 191 h and the second sub-pixel electrode191 l respectively include partial plate electrodes 192 h and 192 lpositioned at a center thereof, and a plurality of minute branchelectrodes 193 h and 193 l protruding from the partial plate electrodes192 h and 192 l in an oblique direction.

The first sub-pixel electrode 191 h includes the first partial plateelectrode 192 h and a plurality of first minute branch electrodes 193 h,and is connected to the wide end of the drain electrode 175 outside thesquare region.

The first partial plate electrode 192 h has a rhombus shape, and eachvertex of the rhombus meets the boundary of the square region. The firstpartial plate electrode 192 h covers the first step providing groove 185h and the first cross-shaped protrusion 182 h of the passivation layer.As a result, the first partial plate electrode 192 h has the stepprovided by the first step providing groove 185 h of the passivationlayer 180 and the first cross-shaped protrusion 182 h. Here, the firstcross-shaped protrusion 182 h provides the pretilt to the liquid crystalmolecules positioned at the center of the square region, thereby havinga function of controlling an arrangement direction of the liquid crystalmolecules, and as a result, texture is reduced. A plurality of firstminute branch electrodes 193 h extend in the edge of the obliquedirection of the first partial plate electrodes 192 h. A plurality offirst minute branch electrodes 193 h form an angle of 45 degrees withrespect to the gate line 121 or the data line 171, and form an angle of90 degrees with respect to the edge of the oblique direction of thefirst partial plate electrode 192 h.

The second sub-pixel electrode 191 l includes the second partial plateelectrode 192 l and a plurality of second minute branch electrodes 193l, and overlaps the auxiliary electrode 176 thereby forming theassistance capacitor Cas.

The second partial plate electrode 192 l has a rhombus shape connectingeach edge of the rectangle region. As a result, each of the vertices ofthe rhombus meets the boundary of the rectangle region. The secondpartial plate electrode 192 l covers the second step providing groove185 l of the passivation layer and the second cross-type protrusion 182l. As a result, the second partial plate electrode 192 l has the stepprovided by the second step providing groove 185 l of the passivationlayer and the second cross-type protrusion 182 l. A plurality of secondminute branch electrodes 193 l extend from the edge of the obliquedirection of the second partial plate electrode 192 l. A plurality ofsecond minute branch electrodes 193 l fill the rest of the region of therectangle region, form an angle of 45 degrees with respect to the gateline 121 or the data line 171, and form an angle of 90±15 degrees withrespect to the edge of the oblique direction of the second partial plateelectrode 192 l.

The first and second sub-pixel electrodes 191 h and 191 l form the firstand second liquid crystal capacitors along with the common electrode ofthe upper panel and the liquid crystal layer therebetween to maintainthe applied voltage after the thin film transistor (Q of FIG. 25) isturned off.

The first and second sub-pixel electrodes 191 h and 191 l overlap thestorage electrodes 135 a and 135 b to form the first and second storagecapacitors Csta and Cstb, thereby reinforcing the voltage storagecapacity of the first and second liquid crystal capacitors Clca andClcb.

In the first exemplary embodiment, the auxiliary electrode 176 extendsfrom the drain electrode 175, but the present invention is not limitedthereto, and the auxiliary electrode 176 may be separated from the drainelectrode 175. At this time, the passivation layer includes a contacthole formed on the first sub-pixel electrode 191 h, and the auxiliaryelectrode 176 may be connected to the first sub-pixel electrode 191 hthrough the contact hole and may overlap the second sub-pixel electrode191 l.

Hereinafter, referring to FIG. 27 and FIG. 28, after two sub-pixelsrespectively receive the same data voltage from the transistors Qa andQb, the charge of the second sub-pixel electrode (191 l of FIG. 28)flows to the assistance capacitor Cas of the third switching element Qcsuch that the voltage of the second liquid crystal capacitor Clcb isdecreased.

The liquid crystal display according to an exemplary embodiment of thepresent invention will be described with reference to FIG. 27 and FIG.28.

FIG. 27 is an equivalent circuit diagram of one pixel of a liquidcrystal display according to an exemplary embodiment of the presentinvention, and FIG. 28 is a layout view of a lower panel of a liquidcrystal display according to an exemplary embodiment of the presentinvention.

The liquid crystal display according to an exemplary embodiment of thepresent invention includes the signal lines including a plurality ofgate lines GLn and GLn+1, a plurality of data lines DL, and a pluralityof storage voltage lines SL, with a plurality of pixels PX connectedthereto. Each pixel PX includes a pair of the first and secondsub-pixels PXa and PXb, and the first sub-pixel PXa includes the firstsub-pixel electrode (191 h of FIG. 28) while the second sub-pixel PXbincludes the second sub-pixel electrode (191 l FIG. 28).

The liquid crystal display according to an exemplary embodiment of thepresent invention further includes the first switching element Qa andthe second switching element Qb connected to the gate line GLn and thedata line DL, the first liquid crystal capacitor Clca and the firststorage capacitor Csta connected to the first switching element Qa andformed in the first sub-pixel PXa, the second liquid crystal capacitorClcb and the second storage capacitor Cstb connected to the secondswitching element Qb and formed in the second sub-pixel PXb, the thirdswitching element Qc connected to the second switching element Qb andswitched by the gate line GLn+1 of the next stage, and the assistancecapacitor Cas connected to the third switching element Qc.

The first and second switching elements Qa and Qb, as three-terminalelements such as a thin film transistor, etc., and provided on a lowerdisplay panel 100, include control terminals thereof connected to thegate line GLn, input terminals thereof connected to the data line DL,and output terminals thereof connected to the first liquid crystalcapacitor Clca and the first storage capacitor Csta, and the secondliquid crystal capacitor Clcb and the second storage capacitor Cstb,respectively.

The third switching element Qc, which is also a 3-terminal element suchas a thin film transistor and the like provided on the lower displaypanel 100, includes a control terminal connected to the subsequent gateline GLn+1, an input terminal connected to the second liquid crystalcapacitor Clcb, and an output terminal connected to the auxiliarycapacitor Cas.

One terminal of the auxiliary capacitor Cas is connected to the outputterminal of the third switching element Qc and the other terminal isconnected to the storage electrode line SL.

Hereinafter, an operation of the liquid crystal display according to theexemplary embodiment of the present invention will be described. Whenthe gate-on voltage is applied to the gate line GLn, the first andsecond switching elements Qa and Qb that are connected thereto areturned on and the data voltage of the data line 171 is applied to thefirst and second sub-pixel electrodes (191 h and 191 l of FIG. 28).

Subsequently, when a gate-off voltage is applied to the gate line GLnand the gate-on voltage is applied to the subsequent gate line GLn+1,the first and second switching elements Qa and Qb are turned off and thethird switching element Qc is turned on. As a result, electrical chargesof the second sub-pixel electrode (191 l of FIG. 28) connected to theoutput terminal of the second switching element Qb flow into theauxiliary capacitor Cas to reduce the voltage of the second liquidcrystal capacitor Clcb.

As described above, the charged voltages of the first and second liquidcrystal capacitors Clca and Clcb are different from each other toimprove the lateral visibility of the liquid crystal display.

In the structure of the liquid crystal display according to the secondexemplary embodiment of the present invention, a plurality of gateconductors including a plurality of first gate lines 121, a plurality ofsecond gate lines 123, and a plurality of storage electrodes lines 131are formed on an insulation substrate (not shown) which is made oftransparent glass or plastic, as shown in FIG. 28.

The first gate line 121 and the second gate line 123 extend primarily inthe transverse direction and transfer the gate signal. The first gateline 121 includes the first gate electrode 124 a and the second gateelectrode 124 b that protrude upwards. The second gate line 123 includesthe third gate electrode 124 c that protrudes upwards. The first gateelectrode 124 a and the second gate electrode 124 b are connected toeach other to form one protrusion.

The storage electrode line 131 extends primarily in the transversedirection and transfers the predetermined voltage, such as the commonvoltage, or the like. The storage electrode line 131 includes storageelectrodes 135 a and 135 b that extend up and down. In this case, theshapes and layouts of the storage electrode line 131 and the storageelectrodes 137 a and 137 b may be variously changed.

A gate insulating layer (not shown) is formed on the gate conductors121, 123, and 131.

A plurality of semiconductor islands 154 are formed on the gateinsulating layer 140. The semiconductor islands 154 include a firstsemiconductor 154 a disposed on the first gate electrode 124 a, asemiconductor 154 b disposed on the second gate electrode 124 b, and athird semiconductor 154 c disposed on the third gate electrode 124 c.The first semiconductor 154 a and the second semiconductor 154 b may beconnected to each other.

A data conductor including a plurality of data lines 171, a first drainelectrode 175 a, a second drain electrode 175 b, a third sourceelectrode 173 c, and a third drain electrode 175 c is formed on thesemiconductor 154 and the gate insulating layer 140.

The data lines 171 transfer the data signals and extend primarily in thelongitudinal direction, thereby crossing the first gate line 121 and thesecond gate line 123. Each data line 171 includes the first sourceelectrode 173 a and the second source electrode 173 b that extend towardthe first gate electrode 124 a and the second gate electrode 124 b. Thefirst source electrode 173 a and the second source electrode 173 b areconnected to each other.

Each of the first drain electrode 175 a, the second drain electrode 175b, and the third drain electrode 175 c includes one wide end portion andthe other rod-shaped end portion. The rod-shaped end portions of thefirst drain electrode 175 a and the second drain electrode 175 b arepartially surrounded by the first source electrode 173 a and the secondsource electrode 173 b, respectively. The third drain electrode 175 c isalso partially surrounded by the third source electrode 173 c. The wideone end portion of the second drain electrode 175 b is connected to thethird source electrode 173 c. A wide end portion 177 c of the thirddrain electrode 175 c is partially overlapped with an extension portion137 a of the storage electrode line 131 to form an auxiliary capacitorCas.

The first/second/third gate electrode 124 a/124 b/124 c, thefirst/second/third source electrode 173 a/173 b/173 c, and thefirst/second/third drain electrode 175 a/175 b/175 c form onefirst/second/third thin film transistor (TFT) (Qa/Qb/Qc of FIG. 4)together with the first/second/third semiconductor 154 a/154 b/154 c.The channel of the thin film transistor is formed in each semiconductor154 a/154 b/154 c between each source electrode 173 a/173 b/173 c andeach drain electrode 175 a/175 b/175 c.

The passivation layer (not shown) is formed on the data conductors 171,175 a, 175 b, and 175 c and exposed portions of the semiconductors 154a, 154 b, and 154 c. The passivation layer is made of the insulator andhas a flat surface. The step provider providing the step to theoverlying layer is formed in the passivation layer of the insulator, andin FIG. 26, the step providing grooves 185 h and 185 l and thecross-shaped protrusions 182 h and 182 l positioned between the stepproviding grooves 185 h and 185 l are the step provider. As shown inFIG. 28, the step providing grooves 185 h and 185 l have a righttriangle structure and are symmetrical to each other in a diagonaldirection. As a result, the passivation layer includes the cross-shapedprotrusions 182 h and 182 l. The passivation layer includes a pluralityof contact holes 184 a and 184 b respectively exposing the wide ends ofthe first drain electrode 175 a and the second drain electrode 175 b.

The color filter may be formed under the passivation layer.

A plurality of pixel electrodes 191 are formed on the passivation layer.Each pixel electrode 191 includes the first sub-pixel electrode 191 hand the second sub-pixel electrode 191 l formed at predeterminedintervals.

The first sub-pixel electrode 191 h and the second sub-pixel electrode191 l respectively include partial plate electrodes 192 h and 192 lpositioned at a center thereof, and a plurality of minute branchelectrodes 193 h and 193 l protruding from the partial plate electrode192 h and 192 l in an oblique direction.

The first sub-pixel electrode 191 h includes the first partial plateelectrode 192 h and a plurality of first minute branch electrodes 193 h,and is connected to the wide end of the drain electrode 175 a outsidethe region where the first sub-pixel electrode 191 h is formed.

The first partial plate electrode 192 h has a rhombus shape, and eachvertex of the rhombus meets the boundary of the square region. The firstpartial plate electrode 192 h covers the first step providing groove 185h and the first cross-shaped protrusion 182 h of the passivation layer.As a result, the first partial plate electrode 192 h has the stepprovided by the first step providing groove 185 h of the passivationlayer 180 and the first cross-shaped protrusion 182 h. Here, the firstcross-shaped protrusion 182 h provides the pretilt to the liquid crystalmolecules positioned at the center of the square region thereby controlsan arrangement direction of the liquid crystal molecules and, as aresult, texture is reduced. A plurality of first minute branchelectrodes 193 h extend in the edge of the oblique direction of thefirst partial plate electrode 192 h. The plurality of first minutebranch electrodes 193 h form an angle of 45 degrees with respect to thegate lines 121 or the data lines 171, and form an angle of 90 degreeswith respect to the edge of the oblique direction of the first partialplate electrode 192 h.

The second sub-pixel electrode 191 l includes the second partial plateelectrode 192 l and a plurality of second minute branch electrodes 193l, and is connected to the wide end of the second drain electrode 175 boutside the region where the second sub-pixel electrode is formed.

The second partial plate electrode 192 l has a rhombus shape connectingeach edge of the rectangle region. As a result, each of the vertices ofthe rhombus meets the boundary of the rectangle region. The secondpartial plate electrode 192 l covers the second step providing groove185 l of the passivation layer and the second cross-shaped protrusion182 l. As a result, the second partial plate electrode 192 l has thestep provided by the second step providing groove 185 l of thepassivation layer and the second cross-shaped protrusion 182 l. Aplurality of second minute branch electrodes 193 l extend from the edgeof the oblique direction of the second partial plate electrode 192 l. Aplurality of second minute branch electrodes 193 l fill the rest of theregion of the rectangle region, form an angle of 45 degrees with respectto the gate lines 121 or the data lines 171, and form an angle of 90±15degrees with respect to the edge of the oblique direction of the secondpartial plate electrode 192 l.

The first and second sub-pixel electrodes 191 h and 191 l form the firstand second liquid crystal capacitors (Clca and Clcb of FIG. 27) alongwith the common electrode of the upper panel and the liquid crystallayer therebetween to maintain the applied voltage after the thin filmtransistors (Qa and Qb of FIG. 27) are turned off.

The first and second sub-pixel electrodes 191 h and 191 l overlap thestorage electrodes 135 a and 135 b to form the first and second storagecapacitors Csta and Cstb, thereby reinforcing the voltage storagecapacity of the first and second liquid crystal capacitors Clca andClcb.

Hereinafter, referring to FIG. 29 and FIG. 30, a structure in whichdifferent data voltages from the transistors Qa and Qb are respectivelyapplied to two sub-pixels will be described.

FIG. 29 is an equivalent circuit diagram of one pixel of a liquidcrystal display according to an exemplary embodiment of the presentinvention, and FIG. 30 is a layout view of a lower panel of a liquidcrystal display according to an exemplary embodiment of the presentinvention.

Referring to FIG. 29 and FIG. 30, the liquid crystal display accordingto an exemplary embodiment of the present invention includes the lowerpanel 100 and the upper panel 200 facing each other, and the liquidcrystal layer 3 disposed between the two panels 100 and 200.

First, the lower panel 100 will be described.

A plurality of gate lines 121 and a plurality of storage voltage lines131 and 135 are formed on the insulation substrate 110.

The gate lines 121 transmit gate signals, and proceed roughly in thetransverse direction. The gate lines 121 each include a plurality offirst and second gate electrodes 124 a and 124 b protruded upward.

The storage electrode lines include stems 131 extending substantiallyparallel to the gate lines 121, and a plurality of storage electrodes135 protrude from the stems 131.

The shape and disposition of the storage electrode lines 131 and 135 maybe altered in various ways.

A gate insulating layer 140 is formed on the gate lines 121 and thestorage electrode lines 131 and 135, and a plurality of semiconductors154 a and 154 b are formed on the gate insulating layer 140 withamorphous silicon or crystalline silicon.

A plurality of pairs of ohmic contacts (not shown) are formed on thesemiconductors 154 a and 154 b, respectively. The ohmic contacts (notshown) may be formed with silicide, or with n+ hydrogenated amorphoussilicon in which n-type impurities are doped at a high concentration.

A plurality of pairs of data lines 171 a and 171 b and a plurality ofpairs of first and second drain electrodes 175 a and 175 b are formed onthe ohmic contacts (not shown) and the gate insulating layer 140.

The data lines 171 a and 171 b transmit data signals, and proceedroughly in the vertical direction such that they cross the gate lines121 and the stems 131 of the storage electrode lines. The data lines 171a and 171 b include first and second source electrodes 173 a and 173 bbent toward the first and second gate electrode 124 a and 124 b in theshape of a letter U. The first and second source electrodes 173 a and173 b face the first and second drain electrodes 175 a and 175 b aroundthe first and second gate electrodes 124 a and 124 b.

The first and second drain electrodes 175 a and 175 b include one-sideend portions partially surrounded by the first and second sourceelectrodes 173 a and 173 b, body portions extended upwardly from theformer end portions, and opposite-side wide end portions to be connectedwith other layers.

The shape and disposition of the data lines 171 a and 171 b includingthe first and second drain electrodes 175 a and 175 b may be altered invarious manners.

The first and second gate electrodes 124 a and 124 b, the first andsecond source electrodes 173 a and 173 b, and the first and second drainelectrodes 175 a and 175 b form first and second thin film transistors(TFT) Qa and Qb together with the first and second semiconductors 154 aand 154 b, and the channels of the first and second thin filmtransistors Qa and Qb are formed at the first and second semiconductors154 a and 154 b between the first and second source electrodes 173 a and173 b and the first and second drain electrodes 175 a and 175 b.

The ohmic contacts exist only between the underlying semiconductors 154a and 154 b and the overlying data lines 171 a and 171 b and drainelectrodes 175 a and 175 b so as to lower the contact resistancetherebetween. The semiconductors 154 a and 154 b have exposed portionsnot covered by the data lines 171 a and 171 b and the drain electrodes175 a and 175 b, including a portion thereof between the sourceelectrodes 173 a and 173 b and the drain electrodes 175 a and 175 b.

The passivation layer is formed on the data lines 171 a and 171 b, thedrain electrodes 175 a and 175 b, and the exposed semiconductors 154 aand 154 b. The passivation layer is made of an insulator and has a flatsurface. The step provider providing the step to the overlying layer isformed in the passivation layer of the insulator, and in FIG. 26, thestep providing grooves 185 h and 185 l and the cross-shaped protrusions182 h and 182 l positioned between the step providing grooves 185 h and185 l are the step provider. As shown in FIG. 28, the step providinggrooves 185 h and 185 l have a right triangle structure and aresymmetrical to each other in a diagonal direction. As a result, thepassivation layer includes the cross-shaped protrusions 182 h and 182 l.

The color filters may be formed under the passivation layer.

A plurality of pixel electrodes 191 are formed on the passivation layer.Each pixel electrode 191 includes the first sub-pixel electrode 191 hand the second sub-pixel electrode 191 l formed at predeterminedintervals.

The first sub-pixel electrode 191 h and the second sub-pixel electrode191 l respectively include partial plate electrodes 192 h and 192 lpositioned at a center thereof and a plurality of minute branchelectrodes 193 h and 193 l protruding from the partial plate electrode192 h and 192 l in an oblique direction.

The first sub-pixel electrode 191 h includes the first partial plateelectrode 192 h and a plurality of first minute branch electrodes 193 h,and is connected to the drain electrode 175 a outside the region wherethe first sub-pixel electrode 191 h is formed.

The first partial plate electrode 192 h has a rhombus shape, and eachvertex of the rhombus meets the boundary of the square region. The firstpartial plate electrode 192 h covers the first step providing groove 185h and the first cross-shaped protrusion 182 h of the passivation layer.As a result, the first partial plate electrode 192 h has the stepprovided by the first step providing groove 185 h of the passivationlayer 180 and the first cross-shaped protrusion 182 h. Here, the firstcross-shaped protrusion 182 h provides the pretilt to the liquid crystalmolecules positioned at the center of the square region, therebycontrolling an arrangement direction of the liquid crystal moleculesand, as a result, texture is reduced. A plurality of first minute branchelectrodes 193 h extend in the edge of the oblique direction of thefirst partial plate electrode 192 h. The plurality of first minutebranch electrodes 193 h form an angle of 45 degrees with respect to thegate lines 121 or the data lines 171, and form an angle of 90 degreeswith respect to the edge of the oblique direction of the first partialplate electrode 192 h.

The second sub-pixel electrode 191 l includes the second partial plateelectrode 192 l and a plurality of second minute branch electrodes 193l, and is connected to the second drain electrode 175 b outside theregion where the second sub-pixel electrode is formed.

The second partial plate electrode 192 l has a rhombus shape connectingeach edge of the rectangle region. As a result, each of the vertices ofthe rhombus meets the boundary of the rectangle region. The secondpartial plate electrode 192 l covers the second step providing groove185 l of the passivation layer and the second cross-shaped protrusion182 l. As a result, the second partial plate electrode 192 l has thestep provided by the second step providing groove 185 l of thepassivation layer and the second cross-shaped protrusion 182 l. Aplurality of second minute branch electrodes 193 l extend from the edgeof the oblique direction of the second partial plate electrode 192 l. Aplurality of second minute branch electrodes 193 l fill the rest of therectangle region, form an angle of 45 degrees with respect to the gatelines 121 or the data lines 171, and form an angle of 90±15 degrees withrespect to the edge of the oblique direction of the second partial plateelectrode 192 l.

The first and second sub-pixel electrodes 191 h and 191 l form the firstand second liquid crystal capacitors along with the common electrode ofthe upper panel and the liquid crystal layer therebetween to maintainthe applied voltage after the thin film transistors (Q of FIG. 29) areturned off.

The first and second sub-pixel electrodes 191 h and 191 l overlap thestorage electrodes 135 a and 135 b to form the first and second storagecapacitors Csta and Cstb, thereby reinforcing the voltage storagecapacity of the first and second liquid crystal capacitors Clca andClcb.

Hereinafter, referring to FIG. 31 and FIG. 32, a structure in which,after two sub-pixels receive the same data voltage from the transistorsQa and Qb and then a gray scale displayed in each sub-pixel is changedby the capacitors Csa and Csb connected to a power source line to swingthe voltage, will be described.

FIG. 31 is an equivalent circuit diagram of one pixel of a liquidcrystal display according to an exemplary embodiment of the presentinvention, and FIG. 32 is a layout view of a lower panel of a liquidcrystal display according to an exemplary embodiment of the presentinvention.

As shown in FIG. 31, the liquid crystal display according to anexemplary embodiment of the present invention includes the gate line GL,the data line DL, the first power line SL1, the second power line SL2,and the first switching element Qa and the second switching element Qbconnected to the gate line GL and the data line DL.

The liquid crystal display according to an exemplary embodiment of thepresent invention further includes the assistance step-up capacitor Csaand the first liquid crystal capacitor Clca connected to the firstswitching element Qa, and the assistance step-down capacitor Csb and thesecond liquid crystal capacitor Clcb connected to the second switchingelement Qb.

The first switching element Qa and the second switching element Qb aremade of a three terminal element, such as a thin film transistor. Thefirst switching element Qa and the second switching element Qb areconnected to the same gate line GL and the same data line DL to beturned on such that the same data signals are output at the same time.

A voltage that swings with a constant period is applied to the firstpower line SL1 and the second power line SL2. The first low voltage isapplied to the first power line SL1 during the predetermined period (forexample 1H), and the first high voltage is applied to the first powerline SL1 during a next predetermined period. The second high voltage isapplied to the second power line SL2 during the predetermined period,and the second low voltage is applied to the second power line SL2during the next predetermined period. In this case, the first period andthe second period are repeated several times during one frame, such thatthe voltage that swings is applied to the first power line SL1 and thesecond power line SL2. In this case, the first low voltage and thesecond low voltage may be the same, and the first high voltage and thesecond high voltage may be the same.

The assistance step-up capacitor Csa is connected to the first switchingelement Qa and the first power line SL1, and the assistance step-downcapacitor Csb is connected to the second switching element Qb and thesecond power line SL2.

The voltage Va of the terminal (hereinafter referred to as “the firstterminal”) through which the assistance step-up capacitor Csa isconnected to the first switching element Qa is decreased if the firstlow voltage is applied to the first power line SL1, but is increased ifthe first high voltage is applied to the first power line SL1. Next, thevoltage Va of the first terminal is swung according to the swing of thevoltage of the first power line SL1.

The voltage Vb of the terminal (hereinafter referred to as “the secondterminal”’) through which the assistance step-down capacitor Csb isconnected to the first switching element Qb is increased if the secondhigh voltage is applied to the second power line SL2, but is decreasedif the second low voltage is applied to the second power line SL2. Next,the voltage Vb of the second terminal is swung according to the swing ofthe voltage of the second power line SL2.

As described above, although the same data voltage is applied to twosub-pixels, the voltages Va and Vb of the pixel electrodes of twosub-pixels are different according to the magnitude of the voltagesswung in the first and second power lines SL1 and SL2 such that thetransmittance of the two sub-pixels is different, thereby improvinglateral visibility.

Referring to FIG. 32, the structure of the liquid crystal displayaccording to another exemplary embodiment of the present invention willbe described.

A plurality of gate lines 121, a first power line 131 a, and a secondpower line 131 b are formed on the first substrate (not shown) made oftransparent glass or plastic.

The gate line 121 transmits the gate signals and extends mainly in thetransverse direction. The gate line 121 includes the first gateelectrode 124 a protruding upward and the second gate electrode 124 bprotruding downward.

The voltage that is swung with the predetermined period is applied tothe first power line 131 a and the second power line 131 b.

The first low voltage is applied to the first power line 131 a duringthe predetermined period (for example 1H), and the first high voltage isapplied to the first power line 131 a during the next predeterminedperiod. The second high voltage is applied to the second power line 131b during the predetermined period, and the second low voltage is appliedto the second power line 131 b during the next predetermined period. Inthis case, the first period and the second period are repeated severaltimes during one frame, such that the voltage swings are repeatedlyapplied to the first power line 131 a and the second power line 131 b.In this case, the first low voltage and the second low voltage may bethe same, and the first high voltage and the second high voltage may bethe same.

The first power line 131 a may be formed at an upper side based on thegate line 121, and the second power line 131 b may be formed at a lowerside based on the gate line 121.

The gate insulating layer (not shown) is formed on the gate line 121,the first power line 131 a, and the second power line 131 b. Thesemiconductor island (not shown) is formed on the gate insulating layer.The semiconductor is positioned on the first and second gate electrodes124 a and 124 b.

The plurality of data lines 171, the first source electrode 173 a, thesecond source electrode 173 b, the first drain electrode 175 a, and thesecond drain electrode 175 b are formed on the semiconductor and thegate insulating layer.

The data lines 171 transmit the data signals and extend mainly in thelongitudinal direction, thereby intersecting the gate lines 121 and thepower lines 131 a and 131 b. As shown in FIG. 32, the data lines 171 arenot formed to be straight. Each data line 171 includes a first sub-dataline 171 a and a second sub-data line 171 b that are connected to eachother, and the first sub-data line 171 a and the second sub-data line171 b are disposed at different locations. The first sub-data line 171 ais formed along the edge of the pixel electrode 191 adjacent to theright side of the data line 171, and the second sub-data line 171 b isformed along the edge of the pixel electrode 191 adjacent to the leftside of the data line 171.

The first source electrode 173 a and the second source electrode 173 brespectively protrude from the data line 171 on the first gate electrode124 a and the second gate electrode 124 b. The first source electrode173 a and the second source electrode 173 b protrude from the same dataline 171 and thereby receive the same data voltage. The first sourceelectrode 173 a and the second source electrode 173 b may be formed witha “U” shape.

The first drain electrode 175 a is separated from the first sourceelectrode 173 a, and includes the bar-shaped end facing the first sourceelectrode 173 a based on the first gate electrode 124 a and theexpansion extended to partially overlap the first power line 131 a. Thebar-shaped end of the first drain electrode 175 a is partially enclosedby the first source electrode 173 a of the “U” shape. The extension ofthe first drain electrode 175 a is cross-shaped.

The second drain electrode 175 b is separated from the second sourceelectrode 173 b, and includes the bar-shaped end facing the secondsource electrode 173 b based on the second gate electrode 124 b and theexpansion extended to partially overlap the first power line 131 b. Thebar-shaped end of the second drain electrode 175 b is partially enclosedby the second source electrode 173 b of the “U” shape. The extension ofthe first drain electrode 175 a is cross-shaped.

The first gate electrode 124 a, the first source electrode 173 a, andthe first drain electrode 175 a form the first switching element (Qa ofFIG. 31), and the second gate electrode 124 b, the second sourceelectrode 173 b, and the second drain electrode 175 b form the secondswitching element (Qb of FIG. 31).

The passivation layer is formed on the data line 171, the first andsecond source electrodes 173 a and 173 b, and the first and second drainelectrodes 175 a and 175 b. The passivation layer is made of theinsulator and has a flat surface. The step provider providing the stepto the overlying layer is formed in the passivation layer of theinsulator, and in FIG. 32, the step providing grooves 185 h and 185 land the cross-shaped protrusions 182 h and 182 l positioned between thestep providing grooves 185 h and 185 l are the step provider. As shownin FIG. 32, the step providing grooves 185 h and 185 l have a righttriangle structure and are symmetrical to each other in a diagonaldirection. As a result, the passivation layer 180 includes thecross-type protrusions 182 h and 182 l.

The passivation layer includes a first contact hole 181 a exposing aportion of the first drain electrode 175 a and a second contact hole 181b exposing a portion of the second drain electrode 175 b.

The color filter may be formed under the passivation layer.

A plurality of pixel electrodes 191 are formed on the passivation layer.Each pixel electrode 191 includes the first sub-pixel electrode 191 hand the second sub-pixel electrode 191 l formed at predeterminedintervals.

The first sub-pixel electrode 191 h and the second sub-pixel electrode191 l respectively include partial plate electrodes 192 h and 192 lpositioned at a center thereof, and a plurality of minute branchelectrodes 193 h and 193 l protrude from the partial plate electrode 192h and 192 l in an oblique direction.

The first sub-pixel electrode 191 h includes the first partial plateelectrode 192 h and a plurality of first minute branch electrodes 193 h,and is connected to the extension of the first drain electrode 175 a inthe center (the first partial plate electrode 192 h) of the region wherethe first sub-pixel electrode 191 h is formed. The position where thefirst drain electrode 175 a and the first sub-pixel electrode 191 h areconnected is on the first cross-shaped protrusion 182 h in FIG. 32.According to an exemplary embodiment, the first drain electrode 175 aand the first sub-pixel electrode 191 h may be connected through thefirst step providing groove 185 h or at another region.

The first partial plate electrode 192 h has a rhombus shape, and eachvertex of the rhombus meets the boundary of the quadrangle region. Thefirst partial plate electrode 192 h covers the first step providinggroove 185 h and the first cross-shaped protrusion 182 h of thepassivation layer. As a result, the first partial plate electrode 192 hhas the step provided by the first step providing groove 185 h of thepassivation layer 180 and the first cross-shaped protrusion 182 h. Here,the first cross-shaped protrusion 182 h provides the pretilt to theliquid crystal molecules positioned at the center of the quadrangleregion, thereby controlling an arrangement direction of the liquidcrystal molecules and, as a result, texture is reduced. A plurality offirst minute branch electrodes 193 h extend in the edge of the obliquedirection of the first partial plate electrode 192 h. The plurality offirst minute branch electrodes 193 h form an angle of 45 degrees withrespect to the gate lines 121 or the data lines 171, and form an angleof 90±15 degrees with respect to the edge of the oblique direction ofthe first partial plate electrode 192 h.

Meanwhile, the second sub-pixel electrode 191 l includes the secondpartial plate electrode 192 l and a plurality of second minute branchelectrodes 193 l, and is connected to the extension of the second drainelectrode 175 b in the center (the second partial plate electrode 192 l)of the region where the second sub-pixel electrode 191 l is formed. Theposition where the second drain electrode 175 b and the second sub-pixelelectrode 191 l are connected is on the second cross-shaped protrusion182 l in FIG. 32. However, according to an exemplary embodiment, thesecond drain electrode 175 b and the second sub-pixel electrode 191 lmay be connected through the second step providing groove 185 l or atanother region.

The second partial plate electrode 192 l has a rhombus shape connectingeach edge of the quadrangle region. As a result, each of the vertices ofthe rhombus meets the boundary of the quadrangle region. The secondpartial plate electrode 192 l covers the second step providing groove185 l of the passivation layer and the second cross-shaped protrusion182 l. As a result, the second partial plate electrode 192 l has thestep provided by the second step providing groove 185 l of thepassivation layer and the second cross-shaped protrusion 182 l. Aplurality of second minute branch electrodes 193 l extend from the edgeof the oblique direction of the second partial plate electrode 192 l.The plurality of second minute branch electrodes 193 l fill the rest ofthe rectangle region, form an angle of 45 degrees with respect to thegate lines 121 or the data lines 171, and form an angle of 90±15 degreeswith respect to the edge of the oblique direction of the second partialplate electrode 192 l.

Although not shown in the drawings, a common electrode (not shown) towhich a constant voltage is applied is formed on a second substrate (notshown) that faces a first substrate while being attached thereto, and aliquid crystal layer (not shown) is formed between the first substrateand the second substrate.

The first sub-pixel electrode 191 a and the second sub-pixel electrode191 b maintain the applied voltage even after the first and secondswitching elements Qa and Qb are in an off state by forming first andsecond liquid crystal capacitors Clca and Clcb in conjunction with thecommon electrode that is formed on the second substrate and the liquidcrystal layer disposed therebetween.

The first sub-pixel electrode 191 a forms the assistance step-upcapacitor (Csa of FIG. 31) along with the first power line 131 a and thepassivation layer disposed therebetween such that the voltage of thefirst liquid crystal capacitor (Clca of FIG. 31) is increased. Thesecond sub-pixel electrode 191 b forms the assistance step-downcapacitor (Csb of FIG. 31) along with the second power line 131 b andthe passivation layer interposed therebetween such that the voltage ofthe second liquid crystal capacitor (Clcb of FIG. 31) is decreased.According to the voltage applied to the power lines 131 a and 131 b, theassistance step-up capacitor (Csa of FIG. 31) decreases the voltage ofthe first liquid crystal capacitor (Clca of FIG. 31), and the assistancestep-down capacitor (Csb of FIG. 31) increases the voltage of the secondliquid crystal capacitor (Clcb of FIG. 31).

The alignment layer may be formed on the first and second substrates ofthe liquid crystal display according to the exemplary embodiment of thepresent invention, and photoalignment (referring to FIG. 44) thatcontrols the alignment direction and alignment angle of the liquidcrystal may be implemented by irradiating light to the alignment layer.

In FIG. 32, the portion B is a region in which texture occurs, andluminance is higher there as compared with the other regions.Accordingly, the texture effect may be decreased by covering thecorresponding portion. Among them, the vertical line portion thatcrosses the center of the first and second sub-pixel electrodes 191 aand 191 b does not have a large difference in the luminance of the otherregion in view of a side and a front thereof because the liquid crystallies at an angle of 0 degrees. On the other hand, the horizontal lineportion that crosses the center of the first and second sub-pixelelectrodes 191 a and 191 b has a large difference in the luminance ofthe other region in view of a side thereof because the liquid crystalstands at an angle of 90 degrees.

Therefore, the first power line 131 a and the second power line 131 bmay be formed so that they cover the horizontal line portion thatcrosses the center of the first sub-pixel electrode 191 a and the secondsub-pixel electrode 191 b, thereby preventing the effect by the texture.

In FIG. 32, the structure of the data line 171 is not formed with astraight shape to cover the texture formed at the edge of the pixel.

That is, the first sub-data line 171 a and the second sub-data line 171b are alternately disposed to be connected to each other. The first andsecond sub-pixel electrodes 191 a and 191 b are divided into an upperpart and a lower part, respectively, the edges of the left sides of theupper parts of the first and second sub-pixel electrodes 191 a and 191 boverlap the first sub-data line 171 a, and the edges of the right sidesof the lower parts of the first and second sub-pixel electrodes 191 aand 191 b overlap the second sub-data line 171 b. Therefore, accordingto this arrangement, the texture that is formed at the edge of the pixelmay be decreased.

As shown in FIG. 1, FIG. 4, FIG. 7, FIG. 17, and FIG. 25 to FIG. 32, asin an exemplary embodiment of the present invention, the structureincluding the partial plate electrode, the minute branch electrode, andthe step provider may be applied to various exemplary embodiments inwhich one pixel is divided into at least two sub-pixels. This may beapplied to a case where one pixel is not divided.

In the following exemplary embodiments, an exemplary embodiment in whichthe step provider such as the opening is formed in the color filter 230will be described with reference to FIG. 33 to FIG. 43.

First, a liquid crystal display according to another exemplaryembodiment of the present invention will be described with reference toFIG. 33 to FIG. 35.

FIG. 33 is a layout view of a liquid crystal display according to anexemplary embodiment of the present invention, FIG. 34 is across-sectional view taken along the line XXXIV-XXXIV of FIG. 33, andFIG. 35 is an equivalent circuit diagram of one pixel of the liquidcrystal display of FIG. 33.

Referring to FIG. 33 and FIG. 34, the liquid crystal display accordingto the present exemplary embodiment includes the lower panel 100 and theupper panel 200 facing each other, a liquid crystal layer 3 interposedbetween the two display panels 100 and 200, and a pair of polarizers(not shown) attached at the outer surfaces of the display panels 100 and200.

Now, the lower panel 100 will be described.

A plurality of gate conductors including a plurality of gate lines 121,a plurality of step-down gate lines 123, and a plurality of storageelectrode lines 131 are formed on an insulation substrate 110.

The gate lines 121 and the step-down gate lines 123 transfer gatesignals and mainly extend in a transverse direction. Each gate line 121includes a first gate electrode 124 h and a second gate electrode 124 lprotruding upward and downward, and each step-down gate line 123includes a third gate electrode 124 c protruding upward. In theexemplary embodiment of FIG. 33, the first gate electrode 124 h and thesecond gate electrode 124 l are connected to each other, thereby formingone protrusion.

The storage electrode lines 131 are mainly extended in the transversedirection, and transfer the predetermined voltage such as the commonvoltage Vcom. The storage electrode line 131 includes the storageelectrodes 135 a, 135 b, and 135 c, and the capacitor electrode 134extending downward. The storage voltage line 131 includes two firstlongitudinal storage electrode parts 135 a extending upward, atransverse storage electrode part 135 b connecting the two firstlongitudinal storage electrode parts 135 a, and two second longitudinalstorage electrode parts 135 c further extending upward from thetransverse storage electrode part 135 b.

The first longitudinal storage electrode part 135 a is formed along alongitudinal edge of the first sub-pixel electrode 191 h formed thereon,and the second longitudinal storage electrode part 135 c is formed alongthe longitudinal edge of the second sub-pixel electrode 191 l formedthereon. The transverse storage electrode part 135 b is positionedbetween a transverse edge of the previous second sub-pixel electrode 191l and the transverse edge of the current first sub-pixel electrode 191h, and is formed along the two transverse edges.

As a result, the first longitudinal storage electrode part 135 a and thetransverse storage electrode part 135 b are formed along the edge of thefirst sub-pixel electrode 191 h, thereby at least partially overlappingthe first sub-pixel electrode 191 h, and the second longitudinal storageelectrode part 135 c and the transverse storage electrode part 135 b areformed along the edge of the second sub-pixel electrode 191 l, therebyat least partially overlapping the second sub-pixel electrode 191 l.

In FIG. 33, the overlying transverse storage electrode part 135 b andthe underlying transverse storage electrode part 135 b appear to beseparated from each other, but in actuality, the transverse storageelectrode parts 135 b of the pixels PX that are adjacent up and down areelectrically connected to each other.

A gate insulating layer 140 is formed on the gate conductors 121 and 123and the storage voltage line 131.

A plurality of semiconductors made of hydrogenated amorphous silicon(a-Si), polysilicon, or so on, are formed on the gate insulating layer140. The semiconductors are extend mainly in the vertical direction, andeach semiconductor includes first and second semiconductors 154 h and154 l extending toward the first and second gate electrodes 124 h and124 l and connected to each other, and a third semiconductor 154 cconnected to the second semiconductor 154 l. The third semiconductor 154c is extended, thereby forming a fourth semiconductor 157.

A plurality of ohmic contacts (not shown) are formed on thesemiconductors 154 h, 154 l, and 154 c, wherein the first ohmic contact(not shown) is formed on the first semiconductor 154 h, and the secondohmic contact (not shown) and the third ohmic contact (not shown) arerespectively formed on the second semiconductor 154 l and the thirdsemiconductor 154 c. The third ohmic contact is extended, therebyforming a fourth ohmic contact 167.

A data conductor including a plurality of data lines 171, a plurality offirst drain electrodes 175 h, a plurality of second drain electrodes 175l, and a plurality of third drain electrodes 175 c, is formed on theohmic contacts.

The data lines 171 transmit data signals and extend in the longitudinaldirection, thereby intersecting the gate lines 121 and the step-downgate lines 123. Each data line 171 includes a first source electrode 173h and a second source electrode 173 l extending toward a first gateelectrode 124 h and a second gate electrode 124 l and connected to eachother.

The first drain electrode 175 h, the second drain electrode 175 l, andthe third drain electrode 175 c have one end portion having a wide areaand the other end portion having a linear shape. The bar end portions ofthe first drain electrode 175 h and the second drain electrode 175 l arepartially enclosed by the first source electrode 173 h and the secondsource electrode 173 l. The wide end portion of the second drainelectrode 175 l is again extended thereby forming a third sourceelectrode 173 c having a “U” shape. The wide end portion 177 c of thethird drain electrode 175 c overlaps the capacitor electrode 134,thereby forming the step-down capacitor Cstd, and the bar end portion ispartially enclosed by the third source electrode 173 c.

The first/second/third gate electrode 124 h/124 l/124 c, thefirst/second/third source electrode 173 h/173 l/173 c, and thefirst/second/third drain electrode 175 h/175 l/175 c form afirst/second/third thin film transistor (TFT) Qh/Ql/Qc along with thefirst/second/third semiconductor island 154 h/154 l/154 c, and a channelof the thin film transistor is respectively formed in the semiconductor154 h/154 l/154 c between the source electrode 173 h/173 l/173 c and thedrain electrode 175 h/175 l/175 c.

The semiconductors, including the semiconductors 154 h, 154 l, and 154 cexcept for the channel region between the source electrodes 173 h, 173l, and 173 c and the drain electrodes 175 h, 175 l, and 175 c, havesubstantially the same shape as the data conductors 171, 175 h, 175 l,and 175 c and the first to fourth ohmic contacts. That is, thesemiconductors including the semiconductors 154 h, 154 l, and 154 c havea portion that is exposed without being covered by the data conductors171, 175 h, 175 l, and 175 c, and a portion between the sourceelectrodes 173 h, 173 l, and 173 c and the drain electrodes 175 h, 175l, and 175 c.

A lower passivation layer (not shown) made of an insulator such assilicon nitride or silicon oxide is formed on the data conductors 171,175 h, 175 l, 175 c and the exposed semiconductors 154 h, 154 l, and 154c.

The color filter 230 is positioned on the lower passivation layer (notshown). Each color filter 230 is formed in the longitudinal directionbetween the neighboring data lines 171, and has openings 235 h and 235 loverlapping the first and second sub-pixel electrodes 191 h and 191 l.As shown in FIG. 33, the openings 235 h and 235 l have aright trianglestructure and are symmetrical to each other in the diagonal direction.As a result, the color filter 230 includes a cross-shaped protrusion232. Each color filter 230 may display one of three primary colors suchas red, green, and blue, and the color filters 230 may overlap eachother on the data line 171.

An upper passivation layer 180 q is formed on the lower passivationlayer (not shown) exposed by the openings 235 h and 235 l and the colorfilter 230. The upper passivation layer 180 q prevents peeling of thecolor filter 230, and suppresses contamination of the liquid crystallayer 3 by an organic material of the solvent that flows in from thecolor filter 230, so it prevents defects, such as afterimages, that mayoccur when an image is driven, and may be made of the insulator such assilicon nitride or silicon oxide, or an organic material.

The lower passivation layer (not shown), the color filter 230, and theupper passivation layer 180 q have a plurality of first contact holes185 h and a plurality of second contact holes 185 l respectivelyexposing the wide ends of the first drain electrode 175 h and the seconddrain electrode 175 l.

A plurality of pixel electrodes 191 are formed on the upper passivationlayer 180 q. The pixel electrode 191 includes the first sub-pixelelectrode 191 h and the second sub-pixel electrode 191 l that areseparated based on two gate lines 121 and 123, are disposed up and downthe pixel area, and neighbor each other in the column direction.

The first sub-pixel electrode 191 h and the second sub-pixel electrode191 l respectively include the partial plate electrode 192 h and 192 land a plurality of minute branch electrodes 193 h and 193 l protrudingfrom the partial plate electrode 192 h and 192 l in the obliquedirection.

The first sub-pixel electrode 191 h includes the first partial plateelectrode 192 h and a plurality of first minute branch electrodes 193 hpositioned in the square region and connected to a wide end portion ofthe first drain electrode 175 a by the first connection 197 h extendingoutside the square region.

The first partial plate electrode 192 h has a rhombus shape, a centerthereof is positioned at a center of the square region, and each vertexof the rhombus meets the boundary of the square region. The firstpartial plate electrode 192 h covers the opening 235 h of the colorfilter 230 and the first cross-shaped protrusion 232 h. As a result, thefirst partial plate electrode 192 h has the step provided by the firstopening 235 h of the color filter 230. Here, referring to FIG. 34, afirst cross-shaped protrusion 232 h provides a pretilt to the liquidcrystal molecules positioned at the center of the square region, therebycontrolling an arrangement direction of the liquid crystal moleculesand, as a result, the texture is reduced.

A plurality of first minute branch electrodes 193 h extend in an edge ofthe oblique direction of the first partial plate electrode 192 h. Aplurality of first minute branch electrodes 193 h fill the rest of thesquare region, form an angle of 45 degrees with respect to the gatelines 121 or the data lines 171, and form an angle of 90 degrees withrespect to the edge of the oblique direction of the first partial plateelectrode 192 h.

In the exemplary embodiment of FIG. 33, the first sub-pixel electrode191 h includes the first minute branch connection 194 h connecting thefirst partial plate electrode 192 h and the ends of a plurality of firstminute branch electrodes 193 h in a longitudinal direction or ahorizontal direction. However, according to an exemplary embodiment, thefirst connection 194 h may be omitted, and in this case, a plurality offirst minute branch electrodes 193 h protrude to the outside.

On the other hand, the second sub-pixel electrode 191 l includes thesecond partial plate electrode 192 l and a plurality of second minutebranch electrodes 193 l formed in the rectangle region having alongitudinal edge, and is connected to the wide end portion of thesecond drain electrode 175 l by the second minute branch connection 194l extending outside the rectangle region.

The second partial plate electrode 192 l has a rhombus shape having thelength of all edges being the same, the center thereof is positioned atthe center of the rectangle region, and the left/right vertices of thevertices of the rhombus meet the boundary of the rectangle region.Longitudinal extensions 195 l extending in the vertical direction areconnected at the remaining two vertices of the second partial plateelectrode 192 l, and the other end of the longitudinal extensions 195 lmeets the boundary of the rectangle region. The second partial plateelectrode 192 l covers the second opening 235 l of the color filter 230and the second cross-shaped protrusion 232 l. As a result, the secondpartial plate electrode 192 l has the step provided by the secondopening 235 l of the color filter 230, as shown in FIG. 33 and FIG. 34.A plurality of second minute branch electrodes 193 l extend from theedge of the oblique direction of the second partial plate electrode 192l and two longitudinal extensions 195 l. A plurality of second minutebranch electrodes 193 l fill the rest of the rectangle region, form anangle of 45 degrees with respect to the gate line 121 or the data line171, and form an angle of 90±15 degrees with respect to the edge of theoblique direction of the second partial plate electrode 192 l.

In the exemplary embodiment of FIG. 32, the second sub-pixel electrode191 l includes the second partial plate electrode 192 l and the secondlongitudinal connection 194 l connecting the ends of a plurality ofsecond minute branch electrodes 193 l in the longitudinal direction. Atthis time, the first longitudinal connection 194 h and the first minutebranch electrode 193 h form an angle of 45 degrees. However, accordingto an exemplary embodiment, the second longitudinal connection 194 l maybe omitted and, in this case, a plurality of second minute branchelectrodes 193 l protrude outside.

The first sub-pixel electrode 191 h and the second sub-pixel electrode191 l receive the data voltage from the first drain electrode 175 h andthe second drain electrode 175 l through the first contact hole 185 hand the second contact hole 185 l. The first sub-pixel electrode 191 hand the second sub-pixel electrode 191 l to which the data voltage isapplied generate an electric field in conjunction with the commonelectrode 270 of the common electrode panel 200 to determine a directionof the liquid crystal molecules of the liquid crystal layer 3 betweenthe two electrodes 191 and 270. As described above, according to thedetermined direction of the liquid crystal molecules, the luminance oflight that passes through the liquid crystal layer 3 is changed.

The first sub-pixel electrode 191 h and the common electrode 270 formthe first liquid crystal capacitor Clch in conjunction with the liquidcrystal layer 3 therebetween, and the second sub-pixel electrode 191 land the common electrode 270 form the second liquid crystal capacitorClcl in conjunction with the liquid crystal layer 3 therebetween, sothat the applied voltage is maintained even though the first and secondthin film transistors Qh and Ql are turned off.

The first and second sub-pixel electrodes 191 h and 191 l overlap thestorage electrode 135 and the storage electrode line 131 to form thefirst and second storage capacitors Csth and Cstl, and the first andsecond storage capacitors Csth and Cstl strengthen the voltagemaintaining ability of the first and second liquid crystal capacitorsClch and Clcl.

The capacitor electrode 134 and the wide end portion 177 c of the thirddrain electrode 175 c overlap the gate insulating layer 140 andsemiconductor layers 157 and 167 therebetween to form a voltage dropcapacitor Cstd. In another exemplary embodiment of the presentinvention, the semiconductor layers 157 and 167 that are disposedbetween the capacitor electrode 134 and the wide end portion 177 c ofthe third drain electrode 175 c that constitute the voltage dropcapacitor Cstd may be removed.

The lower alignment layer (not shown) is formed on the pixel electrode191 and the exposed upper passivation layer 180 q. The lower alignmentlayer may be a vertical alignment layer and may include thephoto-reactive material.

The upper panel 200 will be described below.

The light blocking member 220 is positioned under the insulationsubstrate 210. The light blocking member 220 is referred to as a blackmatrix and prevents light leakage. The light blocking member 220 extendsupward and downward according to the gate line 121 and the step-downgate line 123 and covers a region of the first thin film transistor Qh,the second thin film transistor Ql, and the third thin film transistorQc, and extends according to the data line 171 and covers thesurroundings of the data line 171. The region that is not covered by thelight blocking member 220 emits light to the outside, thereby displayingthe images.

The planarization layer 250 providing a planar lower surface and made ofthe organic material is formed under the light blocking member 220.According to the exemplary embodiment of FIG. 34, the light blockingmember 220 is formed in the upper panel 200, although it may be formedin the lower panel 100 according to an exemplary embodiment.

The common electrode 270 made of the transparent conductive material isformed under the planarization layer 250.

The upper alignment layer (not shown) is formed under the commonelectrode 270. The upper alignment layer may be a vertical alignmentlayer and may be an alignment layer in which a photo-polymer material isphoto-aligned.

The polarizers (not shown) are formed on the outer surface of thedisplay panels 100 and 200, the polarization axes of the two polarizersare crossed, and one polarization axis thereof may be parallel to thegate lines 121. Alternatively, the polarizer may be disposed on only oneouter surface among the two display panels 100 and 200.

The liquid crystal layer 3 has negative dielectric anisotropy. Theliquid crystal molecules of the liquid crystal layer 3 are arranged suchthat a longitudinal axis of the liquid crystal molecules may beperpendicular to the surfaces of the two panels 100 and 200 in the casein which an electric field does not exist. Therefore, the incident lightdoes not pass through the crossed polarizers but is blocked in a statein which there is no electric field.

As described above, because the first sub-pixel electrode 191 h and thesecond sub-pixel electrode 191 l to which the data voltage is appliedgenerate an electric field in conjunction with the common electrode 270of the common electrode panel 200, the liquid crystal molecules of theliquid crystal layer 3, which are aligned vertically with respect to thesurfaces of the two electrodes 191 and 270 in a state in which there isno electric field, lie in a horizontal direction with respect to thesurfaces of the two electrodes 191 and 270, and the luminance of lightthat passes through the liquid crystal layer 3 is changed according tothe degree of tilt of the liquid crystal molecules.

The liquid crystal display further includes a spacer (not shown) tomaintain a cell gap between two display panels 100 and 200, and thespacer is attached to the upper panel 200 and may be positioned underthe common electrode 270.

The liquid crystal layer 3 disposed between the lower panel 100 and theupper panel 200 includes liquid crystal molecules 31 having negativedielectric anisotropy.

The liquid crystal layer 3 may further include a polymer that ispolymerized by light, such as ultraviolet rays. The polymer included inthe liquid crystal layer 3 provides the pretilt to the liquid crystallayer 3, and a method providing the pretilt angle will be described indetail in FIG. 44. That is, the liquid crystal layer 3 may not includethe polymer when the arrangement direction is sufficiently controlledwithout the polymer providing the pretilt angle. Meanwhile, according toan exemplary embodiment of the present invention, the alignment layerformed in the upper panel 200 and the lower panel 100 may include thepolymer that is polymerized by the light such as ultraviolet rays, andthe polymer may be included through the method shown in FIG. 44. At thistime, the liquid crystal layer 3 may not include the polymer.

The exemplary embodiment of FIG. 33 includes the upper passivation layer180 q and the lower passivation layer (not shown). That is, the upperpassivation layer 180 q and the lower passivation layer (not shown) areformed on and under the color filter 230, and according to an exemplaryembodiment of the present invention, the upper passivation layer 180 qand the lower passivation layer (not shown) may both be removed or onlyone passivation layer may be removed.

Next, a structure of the color filter and the pixel electrode includingthe characteristics in the liquid crystal display of FIG. 33 will bedescribed with reference to FIG. 36.

FIG. 36 is a layout view only showing a color filter and a pixelelectrode in the liquid crystal display of FIG. 33.

First, FIG. 36 shows the sub-pixel positioned at the upper side of thepixel of FIG. 33, wherein CF indicates the color filter and PE indicatesthe pixel electrode.

The color filter 230 of FIG. 36 has the opening 235. The opening 235includes four portions having the right triangle structure as shown inFIG. 36, disposed diagonally across from each other. As a result, thecross-shaped protrusion 232 is formed through the center of the colorfilter 230. The color filter 230 is removed in the opening 235 of thecolor filter 230, the opening 235 provides the step, and the liquidcrystal molecules are arranged in the predetermined direction by thestep.

The pixel electrode PE shown in FIG. 36 has the followingcharacteristics.

The first sub-pixel electrode 191 h is formed on the color filter 230,the first sub-pixel electrode 191 h has the step provided by the colorfilter 230, and the first partial plate electrode 192 h of the firstsub-pixel electrode 191 h has the step.

The first sub-pixel electrode 191 h includes the first partial plateelectrode 192 h positioned at the center and a plurality of first minutebranch electrodes 193 h protrude from the first partial plate electrode192 h in the oblique direction. The first sub-pixel electrode 191 h isconnected to the wide portion of the first drain electrode 175 h by thefirst connection 197 h extending outside the square region.

The first partial plate electrode 192 h has a rhombus shape and coversfour first openings 235 h of the color filter 230 and the firstcross-shaped protrusion 232 h.

A plurality of first minute branch electrodes 193 h extend in an edge ofthe oblique direction of the first partial plate electrode 192 h andform an angle of 90 degrees by the edge of the oblique direction of thefirst partial plate electrode 192 h. According to an exemplaryembodiment of the present invention, the angle between the edge of theoblique direction of the first partial plate electrode 192 h and thefirst minute branch electrode 193 h may be changed, and may more than 85degrees but less than 95 degrees.

The first sub-pixel electrode 191 h further includes the firstlongitudinal connection 194 h connecting the first partial plateelectrode 192 h and the ends of a plurality of first minute branchelectrodes 193 h in the vertical direction. However, the firstconnection 194 h may be omitted, and in this case, a plurality of firstminute branch electrodes 193 h are protruded outside.

FIG. 36 shows the structure of the sum of the pixel electrode PE and thecolor filter CF, having the step as a result of the opening 235 h of thecolor filter 230. Referring to FIG. 34, with regard to the sum structureCF+PE of the pixel electrode PE and the color filter CF, the edge of therhombus shape of the first partial plate electrode 192 h and the longestedge in the triangle shape of four first openings 235 h of the colorfilter 230 correspond to each other. That is, the longest edge in thetriangle shape of the four first openings 235 h is positioned inside theedge of the rhombus shape of the first partial plate electrode 192 h.

A change of the transmission and the display characteristic by the stepprovided from the color filter will be described.

FIG. 37 and FIG. 38 are views showing an experimental result using anexemplary embodiment of the present invention, where FIG. 37 is theexperimental result of the display characteristic of a case that thestep is not formed and a case that the step is formed, and FIG. 38 isthe experimental result of the display characteristic according tovarious steps.

First, FIG. 37 will be described.

In FIG. 37, (a) shows the display characteristic of the case where thestep is not provided from the underlying layer (for example, the colorfilter) and the pixel electrode includes the partial plate electrode andthe minute branch electrode. Referring to the upper sub-pixel of (a) ofFIG. 37, the texture is formed as a cross-shape through the wide regionsuch that the transmittance is decreased and the luminance is decreasedand, as a result, the texture must be covered such that the apertureratio is decreased.

In contrast, (b) of FIG. 37 shows the display characteristic in the casethat the step is provided. When compared with the case of (a) of FIG.37, although the texture is generated, the cross-shaped texture of thecross type has a relatively narrow width such that the transmittance ishigh and the luminance is high. In FIG. 37, (a) has transmittance about84% and (b) has transmittance of about 87% such that the case ofproviding the step has the preferable transmittance and luminance, andthe aperture ratio may be increased.

In (c) of FIG. 37, in the case of providing the step like in (b) of FIG.37, the arrangement direction of the liquid crystal is controlled in thearrow direction such that the range of the texture generation isdecreased.

When providing the step as in FIG. 37, the display characteristic isimproved, and how the step is provided will be described with referenceto FIG. 38.

FIG. 38 is the experimental result of the display characteristics whenthe step provided from the color filter 230 has the thickness of 1000 Å,2000 Å, 3000 Å, and 4000 Å, and the structure of FIG. 36 is applied.

As shown in FIG. 38, when the step provided from the color filter 230 is1000 Å, the range of the texture generation is very wide. As the step isincreased, the range of the texture generation is decreased, and whenthe step is 4000 Å, the step is only generated in the region of thecross shape. Therefore, the step provided from the color filter 230 maybe more than 4000 Å.

In particular, the cross-shaped protrusion 232 formed in the colorfilter 230 provides the pretilt to the liquid crystal moleculespositioned at the center of the square region, thereby controlling thearrangement direction of the liquid crystal molecules such that it ispreferable that the height of the cross-shaped protrusion 232 is morethan 4000 Å. In that case, the arrangement direction of the liquidcrystal molecules is also controlled in the center of the square region,and the texture may be reduced.

According to an exemplary embodiment, the color filter 230 may not becompletely removed. That is, the opening 235 of the triangle shapeformed in the color filter 230 is not the opening and the color filter230 of the predetermined thickness may be formed with a remaininggroove. The opening and the groove are referred to as “a step provider”hereafter. When the step provider is not the opening, but is instead thegroove, the color filter may be formed with a relatively smallerthickness than the thickness of the surrounding color filter 230 in thegroove of the triangle shape. Also, according to an exemplary embodimentof the present invention, the color filter that is thinly formed in thegroove of the triangle shape may have a thickness that is graduallychanged in at least one direction.

As described above, the exemplary embodiment includes the step provider(the opening or the groove). However, the area displaying white isincreased in the exemplary embodiment where that the color filter 230 iscompletely removed such that the luminance and the transmittance areincreased, and thereby the aperture ratio is also increased.

A pixel structure according to another exemplary embodiment of thepresent invention will be described with reference to FIG. 39 to FIG.42.

FIG. 39 to FIG. 42 are layout views of a part separated from anotherexemplary embodiment of the present invention.

FIG. 39 is the exemplary embodiment in which the size of the opening 235of the color filter 230 and the size of the partial plate electrode 192are small as compared with FIG. 36. As a result, in FIG. 39, the lengthof the minute branch electrode 193 is relatively long and the partialplate electrode 192 is positioned inside the square region such that thelongitudinal extension 195 extending in the vertical direction and thetransverse extension 196 extending in the horizontal direction areformed in the partial plate electrode 192.

The structure of the color filter 230 and the pixel electrode 191according to FIG. 39 is described in detail, and the exemplaryembodiment of FIG. 39 only shows the upper sub-pixel among one pixel.

The color filter 230 is positioned on the substrate 110. The thin filmtransistor may be formed between the color filter 230 and the substrate110. The color filter 230 has the opening 235 h. The opening 235 h has aright triangle structure, and a total of four openings 235 h aredisposed to be symmetrical to each other in the diagonal direction. As aresult, the color filter 230 includes the cross-shaped protrusion 232 h.

The first sub-pixel electrode 191 h is formed on the color filter 230.The first sub-pixel electrode 191 h includes the first partial plateelectrode 192 h positioned at the center and a plurality of first minutebranch electrodes 193 h protruding from the first partial plateelectrode 192 h in the oblique direction. The first sub-pixel electrode191 h includes the first partial plate electrode 192 h and a pluralityof first minute branch electrodes 193 h positioned in the square region,and is connected to the output terminal of the thin film transistor bythe first connection 197 h extending outside the square region.

The first partial plate electrode 192 h has a rhombus shape, and thecenter thereof is positioned at the center of the square region. Howeverthe size thereof is small such that the vertex of the rhombus isseparated from the boundary of the square region by a predetermineddistance. In each vertex of the rhombus of the first partial plateelectrode 192 h, the longitudinal extension 195 h and the transverseextension 196 h respectively extending in the vertical direction and thehorizontal direction are formed and meet the boundary of the squareregion. Here, the line width of the longitudinal extension 195 h and thetransverse extension 196 h may be the same, and may be more than ⅓ andless than 1 times the line width of the protrusion 232 h of the crosstype. In reality, when forming the cross-shaped protrusion 232 h in thecolor filter 230, the cross-shaped protrusion 232 h of the cross typemay have the taper structure. At this time, if the tapered side isprojected to the lower surface (hereinafter referred to as “the linewidth of the tapered side”), the line width of the tapered side may haveabout ⅓ of the width of the lower surface (hereinafter referred to as “atotal line width”), and in this case, the upper surface of the taperedprotrusion 232 h also has the width of about ⅓ of the width of the lowersurface. In this exemplary embodiment, the width of the longitudinalextension 195 h and the transverse extension 196 h may have the width ofthe degree of the upper surface of at least the tapered first protrusion232 h. At this time, the width of the longitudinal extension 195 h andthe transverse extension 196 h may have a value of more than the linewidth of the tapered side surface of the protrusion 232 h to less thanthe entire line width.

Meanwhile, the first partial plate electrode 192 h covers the opening235 h of the color filter 230 and the first cross-shaped protrusion 232h. As a result, the first partial plate electrode 192 h has the stepprovided by the first opening 235 h of the color filter 230. That is,FIG. 39 is a view showing the pixel electrode PE and the color filter CFin a plane view. However, the structure actually has the step because ofthe opening 235 h of the color filter 230. Here, the first cross-shapedprotrusion 232 h controls the arrangement direction of the liquidcrystal molecules positioned at the center of the square region, therebyreducing the texture.

A plurality of first minute branch electrodes 193 h are extended at theedge of the oblique direction of the first partial plate electrode 192h, and at the longitudinal extension 195 h and the transverse extension196 h. A plurality of first minute branch electrodes 193 h fill the restof the square region and form the angle of 90 degrees with respect tothe edge of the oblique direction of the first partial plate electrode192 h, the longitudinal extension 195 h, and the transverse extension196 h.

The first sub-pixel electrode 191 h includes the first longitudinalconnection 194 h connecting the first partial plate electrode 192 h andthe ends of a plurality of first minute branch electrodes 193 h in thevertical direction. At this time, the first longitudinal connection 194h and the first minute branch electrode 193 h form an angle of 45degrees. However, according to an exemplary embodiment of the presentinvention, the first connection 194 h may be omitted, and in this case,a plurality of first minute branch electrodes 193 h protrude to theoutside.

According to an exemplary embodiment, the angle formed by the edge ofthe oblique direction of the first partial plate electrode 192 h, thelongitudinal extension 195 h, and the transverse extension 196 h and thefirst minute branch electrode 193 h may be changed in the range of morethan 85 to less than 95 degrees. The angle between the first minutebranch electrode 193 h and the first longitudinal connection 194 h mayhave an angle of more than 40 to less than 50 degrees.

In the exemplary embodiment of FIG. 39, as shown in FIG. 44, the pretiltproviding polymer 350 may be included in the liquid crystal layer 3, andwhen the step provided by the opening 235 h of the color filter 230 andthe pattern of the minute branch electrodes 193 only controls the liquidcrystal molecules and the texture is not decreased, the pretiltproviding polymer 350 may additionally be used.

In the exemplary embodiment of FIG. 39, compared with the exemplaryembodiment of FIG. 33, FIG. 34, and FIG. 36, the size of the opening 235h of the color filter 230 is small. However, the opening 235 h that isnot formed in the color filter 230 is formed such that the whiteluminance is high and the texture is reduced by controlling the liquidcrystal molecules such that the portion to be covered is reduced,thereby resulting in an increase in the aperture ratio and thetransmittance.

FIG. 40 only shows the lower sub-pixel of one pixel, and when comparedwith FIG. 33, the size of the opening 235 l of the color filter 230 andthe size of the partial plate electrode 192 l are the same. However, thenumber of openings 235 l and the number of partial plate electrodes 192l is twice that shown in FIG. 33. As a result, in FIG. 40, the number ofopenings 235 l that are not formed in the color filter 230 is increasedsuch that the white luminance is high, and the aperture ratio and thetransmittance are high.

The structure of the color filter 230 and the pixel electrode 191according to FIG. 40 will now be described in detail.

The color filter 230 is positioned on the substrate 110. The thin filmtransistor may be formed between the color filter 230 and the substrate110. The color filter 230 has the opening 235 l. The opening 235 l hasthe right triangle structure, and includes an opening 235 l group thatis symmetrically arranged in pairs. A total of four openings 235 l aredisposed to be symmetrical to each other in the diagonal direction, andthe cross-shaped protrusion 232 l is formed by the opening 235 l in thecolor filter 230. The opening 235 l groups that are symmetricallyarranged in pairs are disposed up and down, and the cross-shapedprotrusion 232 l is connected into a straight line.

The second sub-pixel electrode 191 l is formed on the color filter 230.The second sub-pixel electrode 191 l is divided in two regions up anddown, a pair of the second partial plate electrodes 192 l and aplurality of second minute branch electrode 193 l are formed for oneregion, and they respectively correspond to the opening 235 l group thatis symmetrically arranged. The two regions divide the rectangle regionup and down, thereby respectively forming the square region.

The second partial plate electrode 192 l and a plurality of secondminute branch electrode 193 l formed in one region will now bedescribed.

The second partial plate electrode 192 l positioned at the center of oneregion and a plurality of second minute branch electrodes 193 lprotruding from the second partial plate electrode 192 l in the obliquedirection are included. The second sub-pixel electrode 191 l includesthe second partial plate electrode 192 l positioned in the square regionand a plurality of second minute branch electrodes 193 l.

The second partial plate electrode 192 l has the rhombus shape, thecenter thereof is positioned at the center of the square region, andeach vertex of the rhombus meets the boundary of the square region.

The second partial plate electrode 192 l covers the second opening 235 lof the color filter 230 and the second cross-shaped protrusion 232 l. Asa result, the second partial plate electrode 192 l has the step providedby the second opening 235 l of the color filter 230. That is, FIG. 40 isa view showing the pixel electrode PE and the color filter CF in a planeview, having the step formed by the opening 235 l of the color filter230. Here, the second cross-shaped protrusion 232 l controls thearrangement direction of the liquid crystal molecule positioned at thecenter of the square region, thereby reducing the texture.

A plurality of second minute branch electrodes 193 l extend from theedge of the oblique direction of the second partial plate electrode 192l. The plurality of second minute branch electrodes 193 l fill the restof the square region and form an angle of 90 degrees with respect to theedge of the oblique direction of the second partial plate electrode 192l.

The second sub-pixel electrode 191 l includes the second longitudinalconnection 194 l connecting the second partial plate electrode 192 l andthe ends of a plurality of second minute branch electrodes 193 l in thevertical direction. The second longitudinal connection 194 l and thesecond minute branch electrode 193 l form an angle of 45 degrees.However, according to an exemplary embodiment of the present invention,the second longitudinal connection 194 l may be omitted, and a pluralityof second minute branch electrode 193 l may protrude outside.

According to an exemplary embodiment of the present invention, the anglebetween the edge of the oblique direction of the second partial plateelectrode 192 l and the second minute branch electrode 193 l may bechanged, and may be more than 85 degrees to less than 95 degrees. Theangle between the second minute branch electrode 193 l and the secondlongitudinal connection 194 l may be changed to be more than 40 degreesto less than 50 degrees.

A pair of the second partial plate electrodes 192 l respectively formedin two regions of the second sub-pixel electrode 191 l and a pluralityof second minute branch electrodes 193 l are connected by the secondlongitudinal connection 194 l and have the symmetrical structure by thesecond longitudinal connection 194 l. The second longitudinal connection194 l is formed along the boundary of two up and down regions. Theopening 235 l formed in the color filter 230 is positioned at thesymmetrical position by the second longitudinal connection 194 l in theplane view. According to an exemplary embodiment of the presentinvention, the second longitudinal connection 194 l may be omitted, andthe second partial plate electrodes 192 l and the second minute branchelectrodes 193 l may be respectively connected directly to each other.The second partial plate electrode 192 l, a plurality of second minutebranch electrodes 193 l, and the opening 235 l have a structure that issymmetrical with respect to an imaginary line (a line dividing the twoup and down regions) formed at the position of the second longitudinalconnection 194 l.

The second sub-pixel electrode 191 l may be connected to the outputterminal of the thin film transistor by the second connection 197 lextending from the second partial plate electrode 192 l or a pluralityof second minute branch electrode 193 l in the upper direction.

In the exemplary embodiment of FIG. 40, as shown in FIG. 44, the pretiltproviding polymer 350 may be included in the liquid crystal layer 3, andwhen the step provided by the opening 235 l of the color filter 230 andthe pattern of the minute branch electrode 193 controls only the liquidcrystal molecules and the texture is not decreased, the pretiltproviding polymer 350 may additionally be used.

In the exemplary embodiment of FIG. 40, the number of openings 235 h inthe color filter 230 is twice that of the exemplary embodiment of FIG.33, FIG. 34, and FIG. 36, such that the white luminance is high and thetexture is reduced by controlling the liquid crystal molecules and,thereby, the portion to be covered is reduced, resulting in an increasein both the aperture ratio and the transmittance.

The exemplary embodiment of FIG. 41 shows only the lower sub-pixel ofone pixel, as in FIG. 40, and compared with FIG. 40, the size of theopening 235 l of the color filter 230 and the size of the partial plateelectrode 192 l are relatively small. As a result, in FIG. 40, thelength of the minute branch electrode 193 l is relatively long, and thelongitudinal extension 195 l extending from the partial plate electrode192 l in the vertical direction and the transverse extension 196 lextending in the horizontal direction are formed.

The structure of the color filter 230 and the pixel electrode 191according to FIG. 41 will be described in detail below.

The color filter 230 is positioned on the substrate 110. The thin filmtransistor may be formed between the color filter 230 and the substrate110. The color filter 230 has the opening 235 l. The opening 235 l hasthe right triangle structure, and an opening 235 l group that issymmetrically arranged in pairs is included. However, the size of theopening 235 l is smaller than that of the exemplary embodiment of FIG.40. In one opening 235 l group, a total of four openings 235 l aredisposed to be symmetrical to each other in the diagonal direction, andthe cross-shaped protrusion 232 l is formed by the opening 235 l in thecolor filter 230. The opening 235 l group that is symmetrically arrangedin pairs is disposed up and down, and the cross-shaped protrusion 232 lis connected in a straight line.

The second sub-pixel electrode 191 l is formed on the color filter 230.The second sub-pixel electrode 191 l is divided into two up and downregions, a pair of the second partial plate electrodes 192 l and aplurality of second minute branch electrodes 193 l are formed for oneregion, and they respectively correspond to one opening 235 l group thatis symmetrically arranged. The two regions divide the rectangle regionup and down, thereby respectively forming the square region.

The second partial plate electrode 192 l and a plurality of secondminute branch electrodes 193 l formed in one region will now bedescribed.

The second partial plate electrode 192 l positioned at the center of oneregion and a plurality of second minute branch electrodes 193 lprotruding from the second partial plate electrode 192 l in the obliquedirection are included. The second sub-pixel electrode 191 l includesthe second partial plate electrode 192 l positioned in the squareregion, and a plurality of second minute branch electrodes 193 l.

The second partial plate electrode 192 l has the rhombus shape and thecenter thereof is positioned at the center of the square region.However, the size thereof is small such that each vertex of the rhombusis separated from the boundary of the square region by a predetermineddistance. In each vertex of the rhombus of the second partial plateelectrode 192 l, the longitudinal extension 195 l and the transverseextension 196 l respectively extending in the vertical direction and thehorizontal direction are formed and meet the boundary of the squareregion. Here, the line width of the longitudinal extension 195 l and thetransverse extension 196 l may be the same, and may have a size of morethan ⅓ and less than 1 times that of the line width of the cross-shapedprotrusion 232 l. In reality, when forming the cross-shaped protrusion232 l in the color filter 230, the cross-shaped protrusions 232 l havethe taper structure. If the tapered side is projected to the lowersurface (hereinafter, referred to as “the line width of the taperedside”), the line width of the tapered side may have about ⅓ of the widthof the lower surface (hereinafter, referred to as “a total line width”),and in this case, the upper surface of the tapered protrusion 232 l alsohas the width of about ⅓ of the width of the lower surface. In thisexemplary embodiment of the present invention, the width of thelongitudinal extension 195 l and the transverse extension 196 l may havethe width similar to that of the upper surface of at least taperedprotrusion 232 l. The width of the longitudinal extension 195 l and thetransverse extension 196 l may have a value of more than the line widthof the tapered side surface of the protrusion 232 n to less than theentire line width.

The first partial plate electrode 192 l covers the opening 235 l of thecolor filter 230 and the second cross-shaped protrusion 232 l. As aresult, the second partial plate electrode 192 l has the step providedby the first opening 235 l of the color filter 230. That is, FIG. 41 isa view showing the pixel electrode PE and the color filter CF in a planeview. However, the structure has the step because of the opening 235 lof the color filter 230. Here, the second cross-shaped protrusion 232 lcontrols the arrangement direction of the liquid crystal moleculespositioned at the center of the square region, thereby reducing thetexture.

A plurality of second minute branch electrodes 193 l extend in the edgeof the oblique direction of the second partial plate electrode 192 l,and the second longitudinal extension 195 l and the second-firsttransverse extension 196′l. A plurality of second minute branchelectrodes 193 l fill the rest of the square region and form the angleof 90 degrees with respect to the edge of the oblique direction of thesecond partial plate electrode 192 l, the second longitudinal extension195 l, and the second-first transverse extension 196′l.

The second sub-pixel electrode 191 l includes the second longitudinalconnection 194 l connecting the second-first transverse extension 196′land the ends of a plurality of second minute branch electrodes 193 l inthe vertical direction. The second longitudinal connection 194 l and thesecond minute branch electrode 193 l form an angle of 45 degrees.However, according to an exemplary embodiment of the present invention,the second longitudinal connection 194 l may be omitted, and in thiscase, a plurality of second minute branch electrodes 193 l protrudeoutside.

According to an exemplary embodiment of the present invention, the angleformed by the edge of the oblique direction of the second partial plateelectrode 192 l and the second minute branch electrode 193 l may bechanged in the range of more than 85 degrees to less than 95 degrees.The angle between the second minute branch electrode 193 l and thesecond longitudinal connection 194 l may have an angle of more than 40degrees to less than 50 degrees.

A pair of the second partial plate electrodes 192 l respectively formedin two regions of the second sub-pixel electrode 191 l and a pluralityof second minute branch electrodes 193 l are connected by the secondlongitudinal connection 194 l, and have a symmetrical structure isformed by the second longitudinal connection 194 l. The secondlongitudinal connection 194 l is formed along the boundary of two up anddown regions. The opening 235 l formed in the color filter 230 ispositioned at the symmetrical position by the second longitudinalconnection 194 l in the plane view. According to an exemplary embodimentof the present invention, the second longitudinal connection 194 l maybe omitted, and the second partial plate electrodes 192 l and the secondminute branch electrodes 193 l may be respectively connected directly toeach other. The second partial plate electrode 192 l, a plurality ofsecond minute branch electrodes 193 l, and the opening 235 l have astructure that is symmetrical with respect to an imaginary line (a linedividing the two up and down regions) formed at the position of thesecond longitudinal connection 194 l.

The second sub-pixel electrode 191 l may be connected to the outputterminal of the thin film transistor, and may have the structureconnected by the second connection 197 l extending from the secondpartial plate electrode 192 l or a plurality of second minute branchelectrodes 193 l in the upper direction.

In the exemplary embodiment of FIG. 41, as shown in FIG. 44, the pretiltproviding polymer 350 may be included in the liquid crystal layer 3, andwhen only the step provided by the opening 235 l of the color filter 230and the pattern of the minute branch electrodes 193 controls the liquidcrystal molecules and the texture is not decreased, the pretiltproviding polymer 350 may additionally be used.

In the exemplary embodiment of FIG. 40, the number of openings 235 h ofthe color filter 230 is twice that of the exemplary embodiment of FIG.33, FIG. 34, and FIG. 36, such that the white luminance is high and thetexture is reduced by controlling the liquid crystal molecules such thatthe portion to be covered is reduced, and, as a result, the apertureratio and the transmittance are increased.

In FIG. 42, the step provider 235 of the color filter 230 has a rhombusshape, and the upper common electrode 270 has the cross shaped opening275.

The exemplary embodiment of FIG. 42 will be described below.

The color filter 230 is positioned on the lower substrate 110. The thinfilm transistor may be formed between the color filter 230 and thesubstrate 110. The color filter 230 has the opening 235 h, as opposed toanother exemplary embodiment, of a rhombus shape, having the length ofall edges the same in the present exemplary embodiment. As a result, asin another exemplary embodiment, the cross-shaped protrusion is notformed on the color filter 230.

The first sub-pixel electrode 191 h is formed on the color filter 230.The first sub-pixel electrode 191 h has the same structure as that ofFIG. 36. That is, the first partial plate electrode 192 h positioned atthe center and a plurality of first minute branch electrodes 193 hprotruding from the first partial plate electrode 192 h in the obliquedirection are included. The first sub-pixel electrode 191 h includes thefirst partial plate electrode 192 h and a plurality of first minutebranch electrodes 193 h positioned in the square region, and isconnected to the output terminal of the thin film transistor by thefirst connection 197 h extending outside the square region.

The first partial plate electrode 192 h has a rhombus shape, a centerthereof is positioned at a center of the square region, and each vertexof the rhombus meets the boundary of the square region.

The first partial plate electrode 192 h covers the first opening 235 hof the color filter 230, and the edge of the oblique direction of thefirst opening 235 h and the edge of the oblique direction of the firstpartial plate electrode 192 h are parallel to each other. As a result,the first partial plate electrode 192 h has the step provided by thefirst opening 235 h of the color filter 230. That is, FIG. 42 is a viewshowing the pixel electrode PE and the color filter CF in a plane view.However, it is actually a structure having a step resulting from theopening 235 h of the color filter 230.

A plurality of first minute branch electrodes 193 h extend in the edgeof the oblique direction of the first partial plate electrode 192 h. Theplurality of first minute branch electrodes 193 h fill the rest of theregion and form an angle of 90 degrees with respect to the edge of theoblique direction of the first partial plate electrode 192 h.

The first sub-pixel electrode 191 h includes the first longitudinalconnection 194 h connecting the first partial plate electrode 192 h andthe ends of a plurality of first minute branch electrodes 193 h in alongitudinal direction or a horizontal direction. The first longitudinalconnection 194 h and the first minute branch electrode 193 h form anangle of 45 degrees. However, according to an exemplary embodiment ofthe present invention, the first longitudinal connection 194 h may beomitted, and in this case, a plurality of first minute branch electrodes193 h may protrude to the outside.

According to an exemplary embodiment, the angle between the edge of theoblique direction of the first partial plate electrode 192 h and thefirst minute branch electrode 193 h may be changed and may be more than85 degrees to less than 95 degrees. The first minute branch electrode193 h and the first longitudinal connection 194 h may form an angle ofmore than 40 degrees to less than 50 degrees.

In the exemplary embodiment of FIG. 42, the common electrode 270positioned under the upper substrate 210 has the opening 275. Theopening 275 of the common electrode 270 is formed corresponding to theposition of the cross-shaped protrusion formed in the color filter 230in another exemplary embodiment. That is, the center of the opening ofthe cross shape is positioned at the center of the square region, andthe opening is extended in the up/down and right/left direction with thesame length such that the center of the opening of the cross shapeaccords with the center of the first partial plate electrode 192 h.

Here, the line width of the opening 275 of the common electrode 270 mayhave a size of more than ⅓ to less than 1 times that of the line widthof the protrusion 232 of the cross shape formed in the color filter 230in another exemplary embodiment, thereby having the line widthcorresponding to the line width of the longitudinal extension 195 andthe transverse extension 196 in another exemplary embodiment.

The opening 275 of the cross shape formed in the common electrode 270controls the arrangement direction of the liquid crystal molecules inthe center region at the lower region provided by the opening 235 h ofthe color filter 230. As a result, the texture that is generated fromthe center of the square region to the cross shape may be maximallyreduced.

In the exemplary embodiment of FIG. 42, as shown in FIG. 44, the pretiltproviding polymer 350 may be included in the liquid crystal layer 3, andat this time, when the step provided by the opening 235 h of the colorfilter 230, the pattern of the minute branch electrode 193, and theopening 275 of the common electrode 270 only control the liquid crystalmolecules but the texture is not decreased, the pretilt providingpolymer 350 may be additionally used.

In the exemplary embodiment of FIG. 42, as compared with anotherexemplary embodiment, the size of the opening 235 h of the color filter230 is large such that the white luminance is high and the texture isreduced by controlling the liquid crystal molecules such that theportion to be covered is reduced, resulting in an increase in theaperture ratio and the transmittance. However, as compared with anotherexemplary embodiment, the common electrode 270 must be etched once toform the opening 275 such that the additional process is required.

In the exemplary embodiment of FIG. 42, as opposed to another exemplaryembodiment, the opening 235 of the color filter 230 has the rhombusshape, and the common electrode 270 has the cross-shaped opening 275.This structure may be applied to another exemplary embodiment of FIG. 39to FIG. 41 as well as the exemplary embodiment of FIG. 33, FIG. 34, andFIG. 36 like FIG. 42, and may also be applied to the lower sub-pixel.The cross-shaped opening 275 of the common electrode 270 is formed atthe position corresponding to the cross-shaped protrusion formed by theopening 235 of the color filter 230 in each exemplary embodiment.

Next, a cross-sectional view of the opening 235 a of the color filter230 according to another exemplary embodiment of the present inventionwill be described with reference to FIG. 43.

FIG. 43 is a cross-sectional view of a color filter according to anotherexemplary embodiment of the present invention.

Comparing the cross-sectional view of FIG. 43 with the cross-sectionalview of FIG. 34, the opening 235 of FIG. 34 does not have the taperstructure such that the side of the opening 235 where the color filter230 is removed has a vertical surface. However, in FIG. 43, the side ofthe opening 235 has an inclined taper structure.

Usually, when forming the opening 235 in the color filter 230, a slighttaper structure is generally generated, and the angle thereof may becontrolled by controlling a process condition or by changing a mask (atransflective mask, a slit mask, etc.). That is, the taper angle (α) inFIG. 43 may be controlled, and the liquid crystal molecule 31 may bearranged while having the pretilt according to the corresponding taperangle (α), thereby reducing the texture. Therefore, as shown in FIG. 44,although the pretilt providing polymer 350 is not included in the liquidcrystal layer 3, the texture may be reduced by controlling the taperangle (α) of the side wall of the opening 235. However, according to anexemplary embodiment of the present invention, in contrast to the casethat the texture may not be reduced although the taper angle (α) of theside wall of the opening 235 is controlled, as shown in FIG. 44, thepretilt providing polymer 350 may be included in the liquid crystallayer 3.

Meanwhile, when forming the opening 235 of the color filter 230, theside wall generally has the inclined structure such that the colorfilter 230 must be sufficiently removed to form the opening 235, withthe color filter 230 completely removed in the opening 235. Referring tothe exemplary embodiments of FIG. 33 to FIG. 42 when considering thispoint, the minimum area of the opening 235 to be provided in onesub-pixel area is about 8%. If the opening 235 is formed to a value ofless than 8%, a portion where the color filter 230 is not completelyremoved may be generated. Referring to the exemplary embodiments of FIG.33 to FIG. 42, the maximum area of the opening 235 to be provided in onesub-pixel area is about 50%. Therefore, the opening 235 may formed withan area ratio of the range of more than 8% to less than 50% in the pixelarea.

In FIG. 43, the cross-shaped protrusion 232 of the color filter 230 hasan inclined taper structure. If the tapered side is projected to thelower surface (hereinafter referred to as “the line width of the taperedside”), the line width of the tapered side may have about ⅓ of the widthof the lower surface (hereinafter referred to as “a total line width”),and in this case, the upper surface of the tapered protrusion 232 alsohas the width of about ⅓ of the width of the lower surface.

As described above, the opening 235 of the color filter 230 is formed asthe step provider. However, the step provider is not limited to theopening and may be formed as a groove. That is, the color filter 230 mayremain with the predetermined thickness to form the groove instead ofthe opening where the color filter 230 is completely removed, therebyforming the step provider.

Meanwhile, the photo-reactive material may be included in the liquidcrystal layer or the alignment layer, and this will be described withreference to FIG. 44.

FIG. 44 is a view of a process for providing a pretilt to liquid crystalmolecules by using a prepolymer that is polymerized by light such asultraviolet rays.

Referring to FIG. 44, firstly, prepolymers 330, such as a monomer thatis polymerized by light, such as ultraviolet rays, are injected alongwith a liquid crystal material between the two display panels 100 and200. The prepolymer 330 may be a reactive mesogen that is polymerized bylight, such as ultraviolet rays.

The data voltage is applied to the first and second sub-pixel electrodesand a common voltage is applied to the common electrode of the upperpanel 200, thereby forming the electric field in the liquid crystallayer 3 between the two display panels 100 and 200. Thus, the liquidcrystal molecules 31 of the liquid crystal layer 3 are inclined in apredetermined direction in response to the electric field.

As described above, if light of ultraviolet rays is irradiated such thatthe liquid crystal molecules 31 of the liquid crystal layer 3 areinclined in the predetermined direction, the prepolymer 330 ispolymerized, and as shown in FIG. 44, the pretilt providing polymer 350is formed. The pretilt providing polymer 350 contacts with the displaypanels 100 and 200. The liquid crystal molecules 31 are determined tohave the alignment direction in the above-described direction whilehaving the pretilt produced by the pretilt providing polymer 350.Accordingly, when the voltage is not applied to the field generatingelectrodes 191 and 270, the liquid crystal molecules 31 are arrangedwith the pretilt of four directions.

As a result, the liquid crystal molecules 31 have the pretilt in fourdirections in each region of the upper and lower sub-pixels among thepixel.

The pretilt using the polymer, as shown in FIG. 44, may be additionallyapplied when the texture is not reduced through the control for theliquid crystal molecules by the step provided by the color filter 230.

In FIG. 44, the liquid crystal layer includes the photo-reactivematerial. However, the alignment layer may include the photo-reactivematerial.

As described above, the partial plate electrode is formed along with theminute pattern in the pixel electrode, thereby increasing the viewingangle and the lateral visibility of the liquid crystal display, as wellas the response speed, and the step provider is provided at the colorfilter or the overlying layer to reinforce the control force of theliquid crystal molecules, thereby reducing the texture generated in thecenter of the pixel.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the invention. Thus, it isintended that the present invention cover the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

What is claimed is:
 1. A liquid crystal display comprising: a substrate;a pixel electrode comprising a partial plate electrode and a pluralityof branch electrodes extending from the partial plate electrode anddisposed on the substrate; and a color filter disposed between thesubstrate and the pixel electrode, the color filter having a stepprovider disposed between the substrate and the pixel electrode, whereinthe step provider is disposed in the color filter as an opening, and thestep provider does not overlap any signal line or any electrode exceptthe pixel electrode.
 2. The liquid crystal display of claim 1, whereinthe color filter comprises a protrusion generated by the step provider.3. The liquid crystal display of claim 2, wherein: the partial plateelectrode has a rhombus shape; the step provider of the color filtercomprises the opening having a triangle shape; and the longest edge ofthe triangle shape of the step provider corresponds to the edge of therhombus shape.
 4. The liquid crystal display of claim 3, wherein theprotrusion generated by the step provider of the color filter has across shape.
 5. The liquid crystal display of claim 4, wherein thelongest edge of the triangle shape of the step provider is positionedinside the edge of the rhombus shape, and the partial plate electrodecovers the step provider.
 6. The liquid crystal display of claim 5,wherein the pixel electrode further comprises a longitudinal connectionconnecting the partial plate electrode and the plurality of branchelectrodes in the vertical direction.
 7. The liquid crystal display ofclaim 5, wherein the pixel electrode further comprises a longitudinalextension extending in the vertical direction or a transverse extensionextending in the horizontal direction from a vertex of the rhombus shapeof the partial plate electrode.
 8. The liquid crystal display of claim5, wherein the partial plate electrode and the plurality of branchelectrodes form an angle of more than 85 to less than 95 degrees.
 9. Theliquid crystal display of claim 5, wherein an area ratio occupied withthe step provider of the color filter is more than 8% to less than 50%in the pixel area.
 10. The liquid crystal display of claim 9, whereinthe step provider of the color filter comprises an inclined side wall.11. The liquid crystal display of claim 5, wherein: the pixel electrodecomprises a first sub-pixel electrode and a second sub-pixel electrode;and the first sub-pixel electrode and the second sub-pixel electrodecomprise the partial plate electrode and the plurality of branchelectrodes.
 12. The liquid crystal display of claim 11, wherein: thefirst sub-pixel electrode is disposed in a square region; and the secondsub-pixel electrode is disposed in a rectangle region.
 13. The liquidcrystal display of claim 12, wherein, in the partial plate electrode ofthe first sub-pixel electrode, each vertex of the rhombus shape meetsthe square region.
 14. The liquid crystal display of claim 12, wherein,in the partial plate electrode of the first sub-pixel electrode, therhombus shape is positioned inside the square region.
 15. The liquidcrystal display of claim 12, wherein the second sub-pixel electrodecomprises two partial plate electrodes.
 16. The liquid crystal displayof claim 15, wherein: the rectangle region is divided into two squareregions; and two partial plate electrodes are respectively formed in thetwo square regions.
 17. The liquid crystal display of claim 12, whereinthe second sub-pixel electrode comprises one partial plate electrode.18. The liquid crystal display of claim 5, further comprising: an uppersubstrate facing the substrate; a common electrode disposed under theupper substrate; and a liquid crystal layer disposed between thesubstrate and the upper substrate and comprising liquid crystalmolecules.
 19. The liquid crystal display of claim 18, wherein theliquid crystal layer comprises a pretilt providing polymer that ispolymerized by light.
 20. The liquid crystal display of claim 1,comprising: an upper substrate facing the substrate; a common electrodedisposed under the upper substrate; and a liquid crystal layer disposedbetween the substrate and the upper substrate and comprising liquidcrystal molecules, and the common electrode has a cross-shaped opening.21. The liquid crystal display of claim 20, wherein: the partial plateelectrode has a rhombus shape; the opening of the color filter has atriangle shape; the longest edge of the triangle shape of the opening ispositioned inside the edge of the rhombus shape such that the partialplate electrode covers the opening; and the center of the cross-shapedopening corresponds with the center of the partial plate electrode.